iPhone SDK 3.1 beta and iPhone OS 3.1 beta are now posted to the iPhone Dev Center. These versions are for development and testing only and should be installed on devices dedicated to iPhone OS 3.1 beta software development. Please read the iPhone OS Pre-Install Advisory and the iPhone SDK 3.1 beta release notes before downloading and installing.
What to expect from iPhone OS 3.1? As of now there is not much info yet, the devs are still tinkering with what was sent to them but a new "Save a Copy" option for 3G S video editing is said to be something to watch out for, it lets the user retain the original film while saving an edited clip. More on this later...