It looks like Apple is moving right along with updates, as the iPhone 2.1 beta 3 firmware has just been seeded to developers. 

The beta is meant for developers to test, only. However, phones that have been updated to this new version cannot be used to develop apps for the App Store. Likewise, once you update, your phone cannot be reverted back to the old version, so update with caution, developers. 

Word has it that the update contains numerous bug fixes and beginning support for background notifications. 

[via TUAW]