Heres something else that Gizmodo posted about this; http://gizmodo.com/5512637/iphone-40s-game-center-matchmaking-leaderboards-and-achievements
So the game center is launching "Later this year". I wish that meant around 4.0 release but my guess is it will arrive in the fall or early winter.
Good! OpenFeint may be the best one (IMO), but I'm getting tired of all the lag. Hope Apple shuts all the others down when they release their game center.
I'm certain OpenFeint and definentaly ngmoco wilk complain, and merge into the Game Center. Or create a revolution!
I hope integration happens smoothly - as much as I love openfeint, I'm sick of signing up for a new service everytime I buy from a new developer.