Let me start out by saying this is my first thread here, so be nice. On to topic: As many people around here, after upgrading to Mountain Lion I was only getting around 30-40% of what I was "promised" (in my case, 2 to 3 hours). Well, today, while messing around a bit, I found out something that made my battery go to 5 hours of estimated time (I am aware it's estimated time, not real time, but it's worth a shot, no? ) What I did was this: Downloaded TinkerTool System Release 2; Went to System, under System Settings, then Screen; Disabled HiDPI mode (hide HiDPI resolutions); Rebooted (logging out might be sufficient but better safe than sorry). This may not be a solution to rMBP owners out there, and I have no idea why my mid-2010 13" MBP had it on, but I did notice that the battery is draining a bit slower and the machine is cooler and quieter. I hope it works for you guys as it is for me. PS: for those wondering, my battery's at around 80% capacity.