I just installed the ATI drivers for my graphics card, and the power saving feature seems pretty good. With it enabled, my battery meter will give me a max time of about 3 hours and 50 minutes. 4 Hours isn't too bad with discrete graphics enabled. What I have noticed is that it jumps around a lot, will say close to 4 hours, then jump to just over 2, then back up to close to 4. Wattages are all over the place in powertop too, ranging from 16 to 30 something. What this is telling me is that the graphics card is being powered down, and rampped back up quite a bit. Is there a function of these drivers (12.11 beta) where I can tell it to take it a bit easy and scale up slower?