Why do some games quickly go viral and others don't?  What kinds of player experience make users tell their friends, "There's an app for that?" Nicole Lazzaro, president of XEODesign, explains how the kinds of choices users get to make in a game result in emotions that drive real engagement in play and self-propelled social distribution. 

Lazzaro maps out the various emotions that users feel when experiencing what she calls "hard fun, easy fun, serious fun, and people fun."  The most popular games will have elements of at least three of these four.  By crafting user interfaces that maximize opportunities for each of these kinds of fun, game developers can raise the stakes, making their games more fun to play and more likely to go viral.

Social networks like Twitter, Facebook, and Flickr all have the capacity to spread new games and enhance game play, and Lazzaro identifies the unique aspects of each that game designers can use to successfully promote new kinds of satisfying play.  Reducing the number of clicks to play or increasing the potential for deepening social bonds through play tend can push your game faster and farther.  And incorporating true social features into your game, where the player's input alters the game experience for many players, is the new frontier of game development in the post-Wii world.