There's been a flurry of reports in the last week suggesting that Windows 7 is erroneously suggesting that batteries need replacing (and a smaller set of users claiming Windows 7 itself has ruined battery capacity). Microsoft's official stance on the issue? Every case it has investigated has been a result of a faulty battery, rather than faulty software.
The ability to interrogate a battery and report on its health is a new feature in Windows 7 (though whether it will work depends on the type of machine you have). It's not surprising that some people react poorly to being told their battery is problematic, especially on a relatively new machine, but Microsoft says on its Windows 7 blog that every case it has investigated has turned up hardware problems rather than a software issue:
Microsoft has received 12 customer service incidents in addition to pulling 8 additional incidents from various forums. To date (for a total of 20 incidents), none of these have shown anything other than degraded batteries.
How have you found battery life in a Windows 7 world? Tell all in the comments.
Windows 7 Battery Notification Messages [Engineering Windows 7]