Windows Server 2008 R2 (i.e. "Windows 7 Server") introduced significant advancements in Server Power Management capabilities. You may never win a Nobel prize for building an application that plays well with Server Power Management policies nor by configuring a power-optimized data-center, but you'll gain lots of respect for returning real green cash savings for your customers. We think that makes lots of of sense for both Developers and IT Professionals.
Gain insight into new and future power management features and learn more about Windows system Power Management via additional resources listed at MSDN Code Gallery.