According to PC World’s TV ad, Windows 7 makes laptop batteries last longer. That’s probably perfectly true – as long as you’re not actually doing anything with your laptop.
In my experience, what you do while on battery power governs how long it lasts – more than any other factor. Word-crunching is probably the most economical thing to do, being online less so, playing music, especially CDs is power-hungry, as are games. I don’t play games, but I do have a hunting sim that wiped out my battery in record time just running the archery applet (just my avatar, a bow and a line of targets), so it seems fair to assume games, with way more going on, will sap the power faster.
I’d really love to see someone force PCW to prove that statement in the real world.
Oh, and is there a reason why the MS TV ads for W7 seem to be aimed at retards? Watch them and see for yourselves. Actually, I think they’re supposed to be aimed at computer virgins, but as so often with MS advertising, they’ve got it wrong (remember the recent ad for the Tupperware-style party to inflict W7 on your friends, or the black guy edited out of some European ads?).