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Although the era of the social network game officially began with the launch of the Facebook Platform in 2007, it wasn’t until 2009 that social network games began to attract the spotlight of mainstream media with the runaway successes of several games. Not surprisingly, since that moment the online gaming industry has been fully occupied with discerning and attempting to replicate the elements that have made those Facebook games fruitful. Both academics and industry members have engaged in a hearty amount of discussion and speculation as to the reasons for the success seen by social network gaming, watching the evolution of the genre as companies have both emerged and retreated from the industry.

Despite the large number of games appearing on Facebook by a variety of publishers and developers almost none have come close to meeting or bypassing the initial pace set by game developer Zynga. Over the course of just a few years, Zynga has built a company valued at over 15 billion USD with over 200 million monthly active users (MAU) of their games (Woo & Raice, 2011). The next closest game developer is EA at 55 million MAU. EA is one of the first developers in the past three years to develop a game, The Sims Social with 28 million MAU, that has come close to average MAU counts—30 to 40 million—of the games released by Zynga (Appdata, 2011). What then is it about Zynga’s games in particular that make them so successful?

In the discussion and literature addressing social network gaming and the reception and success of Zynga’s games in particular, three core features of their structural design stand out that are frequently referenced as reasons for the success of Zynga. First, Zynga’s games are free-to-play. They require no payment by the player to access and participate in the main features of the game. (Helft, 2011; Brown, 2011; Gaudiosi, 2011) Second, Zynga’s games are social. Players perform social interactions as a core part of their playing experience. Therefore, many believe that “. . . the runaway success of the online games from Zynga can largely be attributed to how they bring together acquaintances who otherwise wouldn’t have much to say to one another . . .” (Jackson, 2011). Finally, Zynga’s games offer a continuous stream of engaging gameplay. The game environment Zynga provides engages players by offering them “new and exciting game content” (Lamacraft, 2010).

However, are these the real reasons behind the current success of the Zynga empire? In the course of this paper, through a case study of FrontierVille—now known as The Pioneer Trail—I will further address these three proposed aspect. First, I will argue that Zynga’s games are not explicitly free-to-play. Rather, I argue that Zynga provides the player with an option of paying through currency or through referral value (media value). This drives the games’ viralibility, and thus their popularity. Second, I will illustrate how many of these games do not rely on core designs based around social interactions, but rather structure social interactions so that players interact with their friends in a way that is eerily similar to that of a player interacting with a non-player character (NPC). I will explore how this social construction allows players to experience a desired feeling of sociality, without having to provide the typical level of commitment required for the average social game. And finally, I will argue why I believe many of Zynga’s engaging “games” are not full-fledged games, but exemplify the “gamification of clicking”.

From FrontierVille to The Pioneer Trail
The Pioneer Trail, formerly known as FrontierVille, is a social network game launched in 2010 by Zynga where the player takes on the role of a pioneer in the American Old West. The player can complete actions such as chopping down trees, clearing ground, growing and harvesting crops, raising animals, tending trees, crafting items, clobbering unwanted pests, constructing buildings, and collecting items. The number of activities a player can do at a time is governed by a limited supply of energy, with almost all activities consuming one point of energy. Energy regenerates over time or can be purchased from the store. By engaging in these activities, players have the chance to earn experience points (XP), coins, special collection items, and, in some cases, resources (i.e. wood and food). Coins allow the player to purchase crops, animals, trees, building plans, and decorations from the Market. Wood allows the player to build the buildings bought from the Market with coins. Each building requires a certain amount of wood to construct. Food allows the player to purchase extra energy from the Market.

The game is structured by storylines which are composed of quests, a set of goals following the narrative of the specific storyline. Each quest asks the player to complete specific tasks (e.g. “chop 25 trees on your homestead” or “tend 5 cows”). Some quests require the player to collect items that are only available by asking friends for the item or purchasing the item with Horseshoes. Most quest lines require players to request these items from their friends, and can only request an item once a day. Horseshoes, of which a limited amount can be earned in-game but mostly are purchased with real world currency, allow the players to buy special limited edition items, energy, and, perhaps most valuably, the special quest items mentioned above. Completing these goals yields a variety of rewards, ranging from XP and coin bonuses to unlocking new quest lines.
The game was renamed to The Pioneer Trail in August of 2011 when the new quest line was launched. This new quest line has players following a storyline of a rescue mission similar to that of The Oregon Trail (Cooper, 2011). However, the original mechanics from Frontierville are still the core feature of the game.

Free-to-play
A free-to-play (F2P) game is a game that provides players with an option of playing the game without paying. This does not mean that the game does not set out to generate any revenue, however. Rather most F2P games make their income through “additional content” players can purchase to enhance or extend their basic playing experience. This is commonly referred to as a micro-transaction model. A pay-to-play (P2P) game is, on the contrary, a game that requires players to pay in order to play the game. Traditionally, the online gaming industry has been based around P2P games—such as the MMORPGs World of Warcraft or Star Wars: The Old Republic. However, in recent years the industry has begun to shift from P2P models to F2P model as F2P games have started to become more profitable than their older cousins (P2P). In the past year many games have begun to make the switch, including Lord of the Rings Online or DC Universe Online, and have seen dramatic increases in revenue (Fahey, 2011). When games began to go F2P very surprisingly “gamers who used to knock off full-price games were spending 10 times that amount on virtual doodads, expediting upgrades and premium features” (Brown, 2011). This increase in profit can be attributed to two major changes that F2P introduces: the removal of the monetary barrier that stood between new players trying a developer’s game, and the flexibility that micro-transactions offers for player with different spending habits. In other words, when a game goes free-to-play “two powerful things can happen: first, more people will likely try your game since you’ve made the ‘ante’ zero; and second, you will likely take more total money, since different players can now spend different amounts depending on their engagement and preferences” (Valadares, 2011). Taking this swell of F2P revenue into consideration, it is not surprising that many scholars and industry professionals attribute Zynga’s success to its decision to be F2P (Helft, 2010; Brown, 2011; Gaudiosi, 2011).
On the surface, it does appear that Zynga’s games, including The Pioneer Trail, fill all of the requirements to be classified as using a free-to-play model. It is accurate to say that there is a possibility to play the entire game without ever paying any real currency. At no point in the game does a player “need”to pay money in order to continue the main storyline of The Pioneer Trail. Players can purchase the majority of items needed for quests from the Market for the low revenue actions purchasable by coins or, if the item is not available for purchase in the Market, players can ask their friends to send them the item. It is always a possibility to buy the items as a high revenue action purchase with horseshoes as opposed to requesting friends to send the necessary items, but it is not required. However, this analysis of the situation considers that there is only one form of payment a player can make: monetary value—i.e. paying in real currency. In actuality, there is another form of payment the player can make, and does make, namely a media value measured in a player’s potential to refer new players to the game through word-of-mouth marketing, making Zynga’s model a hybrid between F2P and P2P. Word-of-mouth (WOM) marketing is “marketing a good or service by the message spread by customers where the communications takes place voluntarily and informally between people or groups” (Lee & Lee, 2006). In other words, it’s marketing where a company activates its product through its customers spreading the word. WOM marketing gives customers a secondary value—the customer advertising for the company—to the original monetary value—the customer spending money on the company’s product (Buttle, 1998). In the end, what Zynga has done with their business model is to create a structure that allowed players two options: either pay with a monetary value or pay with a media value by participating in a specified amount of WOM marketing. As one blogger writes, “advertising was free, users were cheap and achieving virality on a massive scale was easy. Zynga jumped on this, cloning and spamming their way to the top” (Fallarme, 2011). In the end the game is not playable if the player does not want “to pay money or pay by participating in referral marketing” or does not have a big enough referral network in order to meet the required quota (see Image 1–1). Zynga found a structure that allowed for the benefits of F2P game such as easy access for new playersand flexible payment options while monetizing their entire player market like a P2P game.

Social
In games based around sociality, players engage in social interactions as a core part of their playing experience. As Ducheneaut & Moore (2004) explain, “the social nature of most recent games has important consequences for their design. Designers want to promote interactions among the players, as they recognize that these encounters are essential to the success of their virtual worlds” (p. 1).However, beyond this initial definition, it is difficult to determine to what extent a game or mechanic is classifiable as “social” or not. Therefore, when addressing whether or not Zynga’s games are successful because they are social, it is important to take into consideration what is implied by the term social. In the case of Zynga, what is most commonly implied by social is interaction of the player with the player’s Facebook friends. Zynga’s games, as stated above, “bring together acquaintances who otherwise wouldn’t have much to say to one another . . .” (Jackson, 2011). Credit card company Discover has announced a sponsorship of a FarmVille game expansion because they believe “[s]ocial games bring people together into virtual communities” (MerchantServiceSales, 2011). But, is the experience provided by Zynga really about bringing people together?

In general, there are two issues to address concerning the structure of sociality in gaming: the formation of communities in response to the game environment (Kolo & Baur, 2004) and how the game mechanics within that game environment force collaboration or opposition within the gameplay of the game environment which often leads to the formation of those communities (Ducheneaut & Moore, 2004, Koster, 2011). As Raph Koster (2011) proposes several types of constructions of players within multiplayer game environments and the mechanics that can create them. There are many scholars that have written on the social aspect of gaming, however I chose Koster’s mechanics as they are one of the most relatable approaches to social network-based games as a genre. There are two in specific that could apply to The Pioneer Trail: “player versus player (parallel play)” and “networks”.
Player versus player (parallel) because players work alongside each other as opposed to in direct competition with each other, and networks because of the social claims of The Pioneer Trail. Most of Koster’s other social mechanics from “networks”, such as “iterative interactions and trust”, “guilds”, “elections”, “influence and fame” (see Koster, 2011) don’t really come into play within The Pioneer Trail environment. Even “trade and contract” (Koster, 2011), which on the surface seems plausible as the game does allow players to send items to each other, can only be found in The Pioneer Trail in a severely simplified form. In fact, players are banned from communal trading on forums and chat (Jacobs & Shivonen, 2011). Although many mechanics aren’t applicable, there are some elements of sociality in the game: “leaderboards”, “helping”, “gifts”, “reciprocity” (see Koster, 2011). Players can, for instance, perform a limited number of actions per day on their neighbors’ homestead. At the same time, however, players can also reject actions performed by friends on their homestead, pushing away the interaction. Because of this it appears that player interaction is more similar to player interaction with non-player characters (NPCs) than with other players.

In addition to Koster’s social mechanics, other game designers have addressed the social nature in games. In relationship to the example of Zynga, Salen & Zimmerman’s (2003) basic approach to social play is also interesting to explore. Salen & Zimmerman argue there are two kinds of social play. The first is internal, within the confines of the game environment as “a product of the formal system of the game” (p. 462). This, as seen through Koster’s gameplay mechanics, is not very present in The Pioneer Trail. The second type is external social play, “social roles brought into the game” from outside the game such as pre-existing friendships and rivalries (Salen & Zimmerman, 2003, p. 462). This type is the type seen within almost all of Zynga’s games as nearly all social mechanics within the game exist by way of pre-existing friendships. In summary, it appears that although the internal play within the constraints of the game design itself is not social, the external social play of pre-existing relationships does make the game social. This then begins to blur into Zynga’s word-of-mouth (WOM) marketing strategy. Exploring this further, it could be argued that the most social aspects of the game are in fact based around the structure of the WOM marketing mechanics. Zynga’s WOM strategy is mostly present in the form of gift giving—giving a friend an item—and gift requesting—requesting an item—both often with instant effortless reciprocity of the gift to the gift giver. Therefore what many may believe to be social mechanics, are actually just the side effects of Zynga implementing a WOM strategy into its games.

Taking all of this into account, it appears that Zynga games are not traditionally social in the sense that they don’t encourage any direct social interaction with other players. Instead, I believe what Zynga’s environments do well is bring people together for a feeling of a shared social presence, play in parallel. As Ducheneaut et. al proposed, perhaps one of the reasons players play is not for direct social cooperation—in fact many of them choose to avoid it. Instead they enjoy the feeling of community received by participating in something alongside others (Tyni et al., 2011). “For most, playing the game is therefore like being ‘alone together’—surrounded by others, but not necessarily actively interacting with them” (Ducheneaut et. al, 2006). Perhaps being “alone together” in The Pioneer Trail environment is what makes the games successful. Instead of bringing people together into direct contact, Zynga quite literally brings people together into a common shared environment where they have full control over the extent of their social interactions.

Gamification of clicking
What constitutes a game? It’s a tricky concept to ultimately define ¹, however, in the broadest sense of the term, a game is “a system in which players engage in an artificial conflict, defined by rules, that results in a quantifiable outcome” (Salen & Zimmerman, 2003, p. 80). In other words, what defines a game is the structure of the game. As McGonigal (2011) explains, “when we’re playing a game, we just know it. There is something essentially unique about the way games structure experience” (pp. 20–21). Jesper Juul (2003) proposes a six characteristic approach to game structure based on the work of Johan Huizinga (1950), Rogier Caillois (1959), Bernard Suits (1978), E.M. Avedon and Brain Suttin-Smith (1981), Chris Crawford (1984), David Kelley (1988), and Katie Salen and Eric Zimmerman (2003). Inspired by these author’s work, Juul proposes a game definition consisting of six points. Games must be (1) “rule-based”. They must have (2) “variable, quantifiable outcomes” that are (3) “assigned different values, some being positive, some being negative”. The player must invest (4) “effort in order to influence the outcome. (I.e. games are challenging.)” and be (5) “attached to the outcome”. Finally, the game must have (6) “negotiable consequences” where “the same game [set of rules] can be played with or without real-life consequences” (Juul, 2003). Based on this definition, is The Pioneer Trail a game?

First, I would argue The Pioneer Trail is not so much rule-based (1) as it is “property-based”. The word “property” refers to a measurable characteristic (much akin to a physical property in physics). Therefore, when I say The Pioneer Trail is property-based, I am saying that it is mostly governed by its own set of physical properties as opposed to created regulations. It takes 60 seconds to grow a clover. This is less a “rule” of a game as it is a “property” of the environment. Take, for instance, the game of basketball. Gravity is not so much a “rule” of basketball as it is a “property” of the environment it is played in. However, that a player cannot run with the ball during the game but instead must always dribble the ball is a rule of basketball, imposed on top of the environment’s properties.

Despite the variety of tasks needing to be performed, The Pioneer Trail does not have many variable outcomes (2). In general, it has one clearly defined outcome that does not involve skill or chance: the quest is either completed or not completed. The decoration is either purchased or not purchased, placed or not placed. There is a slight variety in terms of crops—as once a crop is grown it only remains ripe (ready for harvesting) for a limited amount of time, therefore the player has the outcome of either harvesting the crop in time, or having the crop decay—but it is still quite limited in outcome. For this reason, as there is often at max two outcomes, there are not frequently outcomes that are better than other outcomes (3). Choosing to perform one quest over another quest does not necessarily provide an alternative or better outcome. Choosing one task before another during a quest does not provide an alternative or better outcome. Harvesting all of the planted crops at one time does not provide an alternative or better outcome than harvesting the crops in 15 minute intervals.

Contrary to the previous three characteristics, however, it is true that the player is required to invest effort to complete tasks (4) and the completion of tasks can affect the game state. Completing a task can influence the materials the player has or the state of one of the many non-player characters (NPCs) in the game, such as a relationship quest that appeared with the creation of The Kissing Tree in 2011. However, while performing a quest, it is rare that a player can influence the outcome outside of deciding to either do the quest or to not do the quest. In this way, the player is, at points, attached to the outcome (5). However, this ties in heavily as to whether or not the game can be played without real-life consequences (6) or real-life interactions which affect the reason the player is attached to the outcome. As A.J. Patrick Liszkiewicz (2010) states in his essay on Farmville: “The secret to Farmville’s popularity is neither gameplay nor aesthetics. Farmville is popular because [it] entangles users in a web of social obligations”. The same applies to The Pioneer Trail, and almost all of the social network games of Zynga. These games are not free of real-life consequences as they enforce a sense of obligation and a connection to real-life relationships and reciprocity.

From this analysis it appears that although some aspects of game structure fit with the social network games of Zynga, at the same time, it’s difficult to definitely argue that it is indeed a game. It appears it’s time to find another structure that may be better to equipped to provide a framework for assessing these social network games “that barely [qualify] as a game” (Liszkiewicz, 2010): and I propose gamification.
Gamification is, in its most simple form, “taking things that aren’t games and trying to make them feel more like games” (Jesse Schell quoted in Graft, 2011). It is “the use of game design elements in non-game contexts” (Deterding, 2011, p.2). An example of gamification is the popular mobile application Foursquare: the gamification of being at a location. Users can “check-in” when at a location, earn points, and publically share their presence at this location with friends on Foursquare itself or other social networks like Twitter or Facebook. Foursquare Friends can compete against each other to “check-in” to the most locations or show off personal achievements—such as checking into certain number of locations in one day. Foursquare has fixed-rules—such as: check in at a location, get points, points add to your total score, your total score affects your ranking in the leaderboard—however it still doesn’t have variable outcomes. In this way, although Foursquare has begun to create a game structure around the activity of being at a location, it is still not inclusive of all aspects of game structure, especially separating activities from real-life consequences. Thus it cannot be characterized as a full game.

The same seems to be true for The Pioneer Trail. From this analysis it appears that although some aspects of game structure can be found in the social network games of Zynga, at the same time, it’s difficult to definitely argue that it is indeed a game. But the question is then: what is it gamifying? How is it gamification? I argue that “social network games” like The Pioneer Trail are the “gamification of clicking”. In the end, The Pioneer Trail and many social network games are about clicking. Each activity is accompanied by a timed click which was well noted by Ian Bogost’s Cow Clicker application. The more you click, the further you progress in the game, making timed clicking the main form of engagement with the game with many players performing thousands of clicks every week, and the main strategy for the player is how to economize that clicking and find the most efficient method. Rather than needing to click to explore the environment, the environment is built to accommodate clicking. The graphical overlay and rudimentary storyline work together to create not so much a game, but rather a clever, yet simple, example of the gamification of clicking.

The Pioneer Trail, game or not, as well as many of Zynga’s applications, have attracted huge audiences and have been able to, for the most part, keep those audiences well engaged. There is much to be explored looking at The Pioneer Trail as a form of gamification as opposed to a game that can help analyze how Zynga has created these engaging retentive environments, why gamification appears to work, the effect of selections of game mechanics, and, in the end, beginning to understand the difference between gamification and games.

Conclusion
At the beginning, the initial selection of literature suggested that Zynga’s social network games have seen success due to the fact they are often “free-to-play”, “social”, and have “engaging gameplay”. Through this critical analysis, I have shown that this is not entirely the case. Zynga games are not really free-to-play, but are instead a hybrid between free-to-play and pay-to-play. The games are able to offer the flexibility of a free-to-play game with easy access for new players and flexible payment options, while monetizing—in one way or another—their entire player market like a pay-to-play game. They do this by offering players a hidden choice between paying real currency or paying media value through word-of-mouth marketing—which triggers an incredibly effective viral referral marketing campaign—to continue engaging with the game. Zynga games are also not, per definition, social games.
Instead, once again, they are a hybrid, offering the basic benefits of social gaming—the “alone together” shared experience—while not requiring the same time commitment required by most full-fledge social games (like MMORPGs). By turning player’s friends into resources, the friends become similar to NPCs, entities that can be used when necessary and can be ignored when desired allowing the greatest flexibility possible in multiplayer gaming. Ironically then most of the arguably “social” mechanics are instead actually a result of implementing a basic world-of-mouth marketing strategy as opposed to the design of the experience. Finally, I showed how Zynga games are perhaps not really game, and instead are a perfect example of gamification—specifically the “gamification of clicking”. Instead of having created an engaging independent game environment Zynga has, in fact, done something much more unique: Zynga has created an enjoyable way to better engage an incredible number of people in the act of clicking.

– All images belong to their rightful owner. Academic intentions only. –

References
Appdata (2011, December 11). App Leaderboard and Developer Leaderboard from Sunday, December 11, 2011. Appdata.com. Retrieved from http://www.appdata.com/

Avedon, E.M. & Sutton-Smith, B. (1981). The Study of Games. New York, NY: John Wiley & Sons.

Brown, M. (2011, June 30). In Gaming, Free-to-Play Can Pay. Wired. Retrieved from http://www.wired.com/gamelife/2011/06/free-to-play/

Buttle, F. A. (1998). Word of mouth: understanding and managing referral marketing. Journal of Strategic Marketing, 6(3), 241–254.

Caillois, R. (1961). Man, play, and games. Glencoe, NY: The Free Press (Original work published 1958).

Cooper, D. (2011, August 14). Zynga’s Pioneer Trail is like The Oregon Trail without the typhoid. Engadget. Retrieved from http://www.engadget.com/2011/08/14/zyngas-pioneer-trail-is-like-the-oregon-trail-without-the-typho

Crawford, C. (1984). The Art of Computer Game Design. New York, NY: McGraw-Hill/Osborne Media.

Deterding, S., Khaled, R. Nacke, L.E., & Dixon, D. (2011). Gamification: Toward a Definition. CHI 2011 Gamification Workshop Proceedings. Retrieved from http://gamification-research.org/wp-content/uploads/2011/04/02-Deterding-Khaled-Nacke-Dixon.pdf
Ducheneaut, N. & Moore, R. J. (2004). The social side of gaming: a study of interaction patterns in a massively multiplayer online game. Retrieved from Palo Alto Research Center website: http://www2.parc.com/csl/members/nicolas/documents/CSCW2004-SWG.pdf

Ducheneaut, N., Yee, N., Nickell, E., & Moore, R. (2006). Alone Together? Exploring the Social Dynamics of Massively Multiplayer Online Games. Proceedings of the ACM CHI 2006, 401–416.

Fahey, M. (2011, November 21). What difference did going free-to-play make for DC Universe Online. Kotaku.Retrieved from http://kotaku.com/5861546/what-difference-did-going-free+to+play-make-for-dc-universe-online

Fallarme, D. (2011, November 20) A teardown of Zynga marketing: how Zynga sucks you in and keeps you there. The Marketing Student. Retrieved fromhttp://www.themarketingstudent.com/2011/11/20/a-teardown-of-zynga-marketing-how-zynga-sucks-you-in-and-keeps-you-there/

Gaudiosi, J. (2011, December 7). Zynga IPO shows bigger picture of evolving games business. Forbes. Retrieved from http://www.forbes.com/sites/johngaudiosi/2011/12/07/zynga-ipo-shows-bigger-picture-of-evolving-games-business/

Graft, K. (2011, March 1). GDC 2011: Time to Ditch the Term “Gamification”? Gamasutra. Retrieved from http://www.gamasutra.com/view/news/33315/gdc_2011_time_to_ditch_the_term_.php

Helft, M. (2010, July 24). Will Zynga Become the Google of Games? The New York Times. Retrieved from http://www.nytimes.com/2010/07/25/business/25zynga.html?pagewanted=all

Huizinga, J. (1950). Homo Ludens. Boston, MA: The Beacon Press (Original work published 1938).

Jackson, J. (2011, February 16). Zynga’s Secret to Success: Connecting Casual Friends. PC World. Retrieved from http://www.pcworld.idg.com.au/article/376848/zynga_secret_success_connecting_casual_friends

Jacobs, M. & Shivonen, T. (2011). In Perpetual Beta – On the Participatory Design of Facebook Gaming. Proceedings of Think Design Play, the 5^th international conference of the Digital Research Association. Retrieved fromwww.digra.org/dl/db/11312.19220.pdf

Juul J., (2003). The Game, the Player, the World: Looking for a Heart of Gameness. In M. Copier & J. Raessens (Eds.), Level Up: Digital Games Research Conference Proceedings (pp. 30–45). Retrieved from http://www.digra.org/dl/db/05163.50560

Kelley, D. (1988). The Art of Reasoning. New York, NY: W. W. Norton & Company.

Kolo, C. & Baur, T. (2004). Living a Virtual Life: Social Dynamics of Online Gaming. Game Studies, 4(1). Retrieved from http://www.gamestudies.org/0401/kolo/

Koster, R. (2011, February). Social Mechanics for Social Games. Paper presented at the 2011 Game Developer Conference, San Francisco, CA. Presentation retrieved from http://www.raphkoster.com/wp-content/uploads/2011/02/Koster_Social_Social-mechanics_GDC2011.pdf

Lamacraft, B. (2010, November 23). Why Zynga Games are so Popular on Facebook. Helium. Retrieved from http://www.helium.com/items/2021962-zynga-games

Lee, K. J. & Lee, J. C. (2006). Design of Ubiquitous Referral Marketing: A Business Model and Method. Lecture Notes in Computer Science, 4082, 102–111.

Liszkiewicz, A. J. P. (2010, October 21). Cultivated Play: Farmville. Berfrois. Retrieved fromhttp://www.berfrois.com/2010/10/cultivated-play-farmville

McGonigal, J. (2011). Reality is Broken: Why Games Make Us Better and How They Can Change the World. London, UK: Random House.

MerchantServiceSales (2011, December 2). Discover sponsors Zynga FarmVille game expansion. Merchantservicesales.com. Retrieved from http://www.merchantservicesales.com/news.aspx?DoAction=ReadMore&NewsID=483429384326458

Salen, K. & Zimmerman, E. (2003). Rules of Play. Game Design Fundamentals. Cambridge, MA: MIT Press.

Suits, B. (1978). The Grasshopper. University of Toronto Press.

Tyni, H., Sotamaa, O. & Toivonen, S. (2011) Howdy Partner!: On free-to-play, Sociability and Rhythm Design in FrontierVille. Proceedings of the 15th International Academic MindTrek Conference: Envisioning Future Media Environments, 22–29.

Valadares, J. (2011, July 7). Free-to-play Revenue Overtakes Premium Revenue in the App Store. Flurry. Retrieved from http://blog.flurry.com/bid/65656/Free-to-play-Revenue-Overtakes-Premium-Revenue-in-the-App-Store

Woo, S. & Raice, S. (2011, November 2). EA Invades Zynga’s Turf. The Wall Street Journal. Retrieved from http://online.wsj.com/article/SB10001424052970204528204577012273802347922.html

Ludography

Cow Clicker, I. Bogost, USA, 2010.

DC Universe Online, Sony Online Entertainment, USA, 2011.

Farmville, Zynga, USA, 2009.

Lord of the Rings Online, Microsoft, USA, 2007.

Star Wars, the Old Republic, Bioware, Canada, 2011.

World of Warcraft, Blizzard, USA, 2007.

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