Techradar has an excellent piece on the engineering efforts around Windows 7 battery life. Although the headline is definitely sensationalist and inaccurate, the meat of the article is quite good. An interesting paragraph describes how configuration settings are largely to blame around the lack of amazing battery life.
“Of course, software, devices and how your PC is set-up are to blame for many problems. "We see notebooks out there that we know should have four hour battery life and they only have two hours," says Pat Stemen, the senior program manager of the Windows kernel team. To fix that Microsoft is asking manufacturers to use its energy troubleshooter across the system to check settings that affect battery life. On one notebook, setting USB devices to go into selective suspend added 29 minutes of battery life.”
It’ll be great to here more about this “energy troubleshooter” hopefully.