Ars Technica reports on issues with Windows 7 and battery life on some laptops.
These users claim their batteries were working just fine under Windows XP and/or Windows Vista, and others are saying it occurs on their new Windows 7 PCs… their PC’s battery life is noticeably lower, with some going as far as saying that it has become completely unusable after a few weeks of use. To make matters worse, others are reporting that downgrading back to an earlier version of Windows won’t fix the problem.
The issue was originally reported back in June 2009, long before Windows 7 was actually released.