Truth be told, we’ve been rocking the iOS 4 GM since last week so we can’t confirm this locally. However, lots of people are saying that Gamecenter didn’t make the iOS 4 cut. Apple said Gamecenter was due in “Fall” and didn’t mention it at WWDC so it isn’t surprising to see it missing.
Because of this, the iOS download sizes have changed even though Apple says the OS is the same build. It will be interesting to see if Gamecenter makes the initial iPhone 4 build or if it is released all products at a later time.
That means we’re keeping our Gamecenter versions of the iPhone 4 GM for now. Contact your friendly neighborhood developer for yours.