In the growing pile of reasons why Windows 7 will be a thousand times better than Vista, Microsoft has reported internal power specifications in which they tested an identical laptop playing back DVDs to battery failure. All things equal, the Vista configuration pulled 17.9W of power, while the Windows 7 machine pulled just 13.4W. It might not sound like much, but that's a big deal.
jkOnTheRun reasons that if in Microsoft's scenario the battery had 52 Watt/hours of power, the Vista system would run 3.05 hours. The same system running Windows 7 would run for 4 hours. And that makes sense, given that Microsoft was able to playback DVDs up to an hour longer on Windows 7 systems.
Microsoft tested a multitude of machines and found that while not everyone will gain an hour of battery life, every Windows 7 user coming from Vista would gain a healthy 11% minimum. [Viddler via jkOnTheRun]