Developers of iPhone Apps were told by Apple this Thursday that:
"If your app submission is not compatible with iPhone OS 3.0, it will not be approved"
As explained on techradar all application submissions will need to be compatible with iPhone 3.0 OS. I'm guessing this means quite a few applications may need to be upgraded, and some nice news for iPhone App developers and probably some extra revenue in some cases unless they were nicely coded to begin with...?