I am planning to do the same thing at lunch today. I can't take the battery anymore either. 2.5 hours and i am left with 48% and screen time on has been 1 hour and that was really just for a little on the bus this morning to check facebook and play 2 moves in words with friends. And at work occasionally turn the screen on to purely check the darn battery life.
And my signal is still really poor too.
I fear a replacement might have the same issues and they will charge me a $35 restocking fee they said if I return the device. I truly think that is BS to do when clearly this phone is having problems. I may as well just reactivate my old droid2.