I think social gaming is doomed by default. A person navigates to Facebook or Twitter because each company has identified itself and has locked in to the consumer. Even GhostTown+ has locked in as a personality based around being a social-er Skype. Seeing games and stuff is just a sideshow. People don't go to social networking sites to play games. It's possible to force this behavior (Zynga), but it's been shown and realized that it can't be sustained, and will eventually burn out. (ZYNGA)