You have to understand the difference between compatible with iOS 5 and requires iOS 5. The former just means that the app has been updated (using the iOS 4 SDK) so that it functions properly on iOS 5. The latter means that the app uses a feature that does not exist prior to iOS 5, and therefore that feature and/or the entire app will not work without iOS 5. Apps that use iOS 5-specific features cannot be submitted to the App Store yet.