I downloaded the e-book and have started to read it. This description of Digg as a game rings very true:

"So just how exactly is Digg.com a hidden game? Certainly, it has no swordwielding heroes who save fantasy worlds from evildoers, but it does have more characters than in any video game. With millions of users, Digg has a wide array of personalities contributing to the community. This makes it like a massive multiplayer online roleplaying game, just without the slaying of monsters. There is a clear goal: to get to the front page, and there are obstacles: not getting dugg up and having to keep trying multiple times. There is fierce competition between all Diggers for that top spot. Sometimes, they even attempt to discredit others’ posts by commenting on poor grammar, false information, and duplicate stories. Strategies are used to defeat other players and they are numerous. Just as many plans for Digg domination through friendship exist though. Seeking out the different users and adding them to the “friends” list is among the most popular and most successful methods. In the end, a win is only when a story has hundreds of diggs, regardless of how you go about it. Everyone is striving to be the best at what they do and this keeps them coming back to Digg for more."

The e-book goes on to tell you how to "win" at Digg and notes that "like all games, Digg’s system can be cheated." It also compares YouTube to chess: "there are an infinite number of ways to win in YouTube but it only occurs under certain conditions. Every single method, strategy, and theory leads back to the essential factor: getting people to view your videos." And as for Facebook, it is compared to The Sims: "The object of the game is more to monitor or to guide characters in daily life rather than to win at something. There’s no simple goal in sight but it is all about the process of playing."

It's a fascinating e-book and thanks C. Weng for making it freely available on Lulu!