Update:
Clearly this is a well documented problem, and wtf Apple, you think your trillion dollar pr dept could have come up with a better public response to this.
That said I haven't been able to recreate the problem since the day I got the phone. And even then, if didn't mess with actual performance, just the bars went down a few notches.
So far very happy with the upgrade, particularly the camera. Only 5 mp, but anyone that knows diddly about photos can tell you that's more than enough res for snapshots and 5x7 printouts. The inage quality is darn good and w/out flash it'll snap them off just as fast as I can take them.
Processor is very very snappy as well, and battery life much improved.