Mine is absolutely terrible!
Went to bed with over 40% battery, this morning it was dead and the alarm didn't go off of course so I slept in half an hour...
So I charged back up to 100% - and now within an hour and a bit I'm back down to 77%!! Something is seriously wrong!
It's running hot too. Have quit all running apps, rebooted, turned off photo stream and location services... battery still draining.
Gonna have to try a restore tonight *though I did that last night when I installed iOS5 - not an 'update'.
Hopefully it will be OK this time?