Apple Seeds iOS 4.1 beta, no updates for iPad yet.
2:50 PM Cupertino Time, iOS Developer site seems to have problem. It might be hammered by developers trying to download the SDK and it iOS 4.1.
Game Center now requires iOS 4.1, it was previously included in iOS 4 beta.
Apple has just seeded iOS 4.1 beta to Developers for iPhone 4, iPhone 3GS, iPhone 3G, iPod touch 2nd and 3rd generation. No update for the iPad yet.
Due to this little thing called NDA, information is still scarce. Not sure what changes are added into iOS 4.1 yet.
Developers can grab te iOS SDK 4.1 and iOS 4.1 for their iPhone and iPod touch at Apple Developer Center. As usual, each device running iOS 4.1 beta must be provisioned.