Here is the specs. I've just looked on my phone and it's now available.
This update contains improvements and bug fixes, including:
Japanese langauge support for Siri (availability may be limited during initial rollout)
Photos can now be deleted from Photo Stream
Camera shortcut now always visible on Lock Screen for iPhone 4S, iPhone 4, iPhone 3GS and iPod touch (4th generation)
Camera face detection now highlights all detected faces
Redesigned Camera app for iPad
Genius Mixes and Genius playlists for iTunes Match subscribers
Audio for TV shows and movies on iPad optimized to sound louder and clearer
Podcast controls for playback speed and a 30 second rewind for iPad
Updated AT&T network indicator
Addresses bugs affecting battery life
Fixes an issue that occasionally caused audio to drop for outgoing calls
For information on the security content of this update, please visit this website: http://support.apple.com/kb/HT1222
I've been hearing lots about notification center issues from 5.0.1, and I have experienced them constantly myself. I can't update wirelessly for some strange reason, but does this update fix those notification issues?