Today we're learned that Microsoft was investigating an issue concerning the battery life of notebooks running Windows 7.
Windows 7 users have been complaining about battery problems on Microsoft's official forums since June of last year, months before Redmond pushed out the full, public release Windows 7. Some complain that their battery life has dropped significantly, while others say the OS is suggesting they go as far as to replace their battery with a brand new one.
One user named tigger1962 says,
"Until yesterday it used [to] state that I had 7 hours battery life after a full charge; today after a full charge, it states that I have 4 hours left. I've only had it on now 15 minutes and my charge has now gone down to 2 hours 24 minutes."
Reverting to Windows XP or Vista doesn't work and neither does charging the laptop while it is off or booting to another OS to charge.
Has installing Windows 7 had a negative effect on your battery? Let us know in the comments below!

I seriously doubt 7 hours is the accurate estimate as sometimes I saw I had 9h estimates sometimes on mine.
I think people just expect batteries to last forever. As to the new ones reporting this error, I will put my guess in user error, they are probably doing intensive stuff which they think don't use that much power, but in fact are chewing up more power than they think.
300 charge cycles isn't really much, its less than a year if charged every day.
The battery meter even tells me to consider buying a new battery which is nonsense as it was working fine with XP less than a week before.
I expected a slight drop in life using a newer OS but it seems to be way over the top.
After a bios update i can squeeze out an extra 10min but it's still pretty useless.
Granted i fiddled with the power settings as i always do...
running linux: about 9hrs with full brightness
running xp: about 8.5hrs full brightness
WINDOWS 7 ULTIMATE: 5HRS remaining
yes a significant drop indeed.
M$: DO SOMETHING ABOUT IT
I wouldn't hesitate to say that it hasn't reduced battery life though!