I'm pretty sure I just discovered what might be causing bad battery life for a couple of users. If not, then in the least I found a bug. When brightness is set to manual, i.e, not set to automatic, the brightness will turn to 100% on a wake of the device, but still show the percentage you last set it at. For example, I set my brightness around 50%. If I let the phone lock itself and then unlock, the screen is wayyy brighter after the unlock. But when I go into the display options, it's still set at 50%. Just touch (don't change the sliders position) the brightness slider and you'll see the brightness return to the value you set.