Last week at PDC, Microsoft gave a first glimpse at the next release of Windows - Windows 7.  All sessions from PDC have been posted at https://sessions.microsoftpdc.com/public/timeline.aspx for your viewing pleasure. I’ve highlighted a session that goes into detail into Windows 7 energy efficiency techniques:

• Windows 7: Extending Battery Life with Energy Efficient Applications
  A single application can accidentally halve battery life for the average laptop. This session demonstrates best practices for designing energy efficient applications and shows utilities for diagnosing common application battery life problems. Learn about how Windows 7 makes it easier for developers to design energy-efficient applications which do not negatively impact mobile PC battery life.