Preview at WWDC likely in June, followed by September launch.
Apple Releases Official iPhone 2.0 (5A347) Firmware [Update]
The "1,1" designation is different, however. The significance of this difference is not entirely clear. Despite the same build numbers. the file sizes of the two builds are different. For those who are concerned, you will likely be able to crossgrade to the official release using the same technique as yesterday. We'll post details of this after some testing. The iPhone 2.0 Firmware provides a number of new features and also provides support for the App Store.
Update: Readers should NOT upgrade to the 2.0 Firmware until Apple resolves their server activation issues. If you do upgrade and are unable to connect to the iTunes servers, your iPhone will be left in an unusable state.