According to an article on wired.com, potential new iPhone hopefuls shouldn’t plan on lining up at Apple stores yet as it is most unlikely that iPhone Os 3.0 will be ready for customers to download by Apple’s WWDC 2009, and without iPhone OS 3.0 it is doubtful Apple will release a new iPhone.
They base this conclusion on Apple launch history and conversations they have had with developers. They do however expect Apple will announce their final iPhone 3.0 roadmap at WWDC 2009 and that iPhone OS 3.0 and a new iPhone will probably follow in 3 to 4 weeks or early July.
Developers contacted by Wired apparently agree that many features of iPhone OS 3.0 are ready, Apple has yet to distribute a crucial part of the software for beta testing.