FluidJ, same thing here. I can't figure it out. You have the same exact time frame as me. I take phone off charger at 7:30am. By 12:00 i have to try and fully charge it again to get through the day. I even bought a brand new stock battery and a new extended battery from Seidio (stock size extended battery). I have done every battery saving trick I know. Screen dim, Home only, check e-mail every hour(rather than "as they arrive"), lowest setting on screen shut off, etc, etc. I here people on this site saying they get most of the day and they surf and WIFI all day. I found this battery post from TP2. I even tried most of her tricks but it seemed to be worse. There is something in there that says WM has a glitch and may only allow our battery to charge half way But the only fix is to do a hard reset.
http://rolandsdottir.blogspot.com/20...life-tips.html
Read it, maybe it WILL help you. It didn't help me.