Using Facebook Connect, visitors can play directly on the Petsociety.com Web site, removing the the forced interaction with Facebook itself. You do still have to login, but you aren't forced to play games as part of the Facebook "experience"--rather you can interact with the game and other players through the API.
I've struggled with the idea that an application/game/what-have-you can ever become hugely profitable if it's locked into the Facebook platform. Ultimately, Facebook makes the rules and companies have to abide by their methodology. And limiting your user base strictly to Facebook seems like a risk. Sooner or later you'll need to break out of the Facebook walls and onto the internet itself.
The very positive aspect of this is that Facebook realizes that openness equals more users and theoretically more revenue. It's in their best interest to make Facebook Connect the most prevalent platform for games and applications to flourish online--a realization that many companies have yet to make.
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