Disney recently bought social game developer Playdom for $563 million, while Google is having ongoing negotiations with game companies for its pet project called Google Games (reportedly designed to counter Facebook’s social game dominance). So what exactly is the reason why online social games are so popular?

While consumer behavior does generally follow that pattern, we must remember that a 5-star rating doesn’t necessarily translate to an objective rating of a game.

As of June 2010, there is a total of 70 million players of Facebook’s top application, Farmville and nearly 30 million playing top 2 app Texas Holdem. And that’s just for the top two games.

National Geographic: Italy is a single player PC game consisting of two casual games: Spot It (or Spot the Difference) and Jumble, both utilizing different photos captured by Nat Geo photographers.