I'm down to 16% since 8:00am(last full charge). It's now 5:55pm. Usage 7 Hours, 53 Minutes Standby 10 Hours, 17 Minutes Some Wifi surfing, some 3G surfing, some music, brightness at 50%, played a few app games. Okay so I've felt that my battery hasn't been lasting me until night time, it use to on my old iPhone(2g). But maybe it's because I've been using more of the 3GS lately. I've heard if I gave my iPhone 3GS some battery conditioning, it would be better, so that's what I'm doing now. Thanks.