If you saw Steve Jobs announce iOS 4.1 last week and have been anxiously awaiting the release, today is the day. Apple is now rolling out the iPhone OS update. Just head on over to iTunes and hook up your device and you're all set.
If you were planning on jailbreaking your device with the (old by now) jailbreakme.com exploit you won't want to be updating past iOS 4.0.1. Apple patched that hole in the last 4.0.2 update.
iOS 4.1 brings bug fixes, the Game Center, and HDR to the iPhone's camera which is probably enough of a reason to update.
If you were planning on jailbreaking your device with the (old by now) jailbreakme.com exploit you won't want to be updating past iOS 4.0.1. Apple patched that hole in the last 4.0.2 update.
iOS 4.1 brings bug fixes, the Game Center, and HDR to the iPhone's camera which is probably enough of a reason to update.