iOS 4.1 is now live, bringing:
- Proximity Sensor fix for iPhone 4
- Game Center
- iTunes TV Show Rentals
- Support for Apple’s new social network, Ping, built into the iTunes app
- HDR Photo taking, which automagically cleans up pictures by combining multiple, simultaneously-taken shots into one
- HD Video Uploads to MobileMe/Youtube over WiFi
iTunes in the UK doesn’t seem to have the update yet, but keep checking!