In my article at Enteprise IT Planet, I pointed out some of tweaks the Windows 7 team has made since the beta (build 7000) according to an MSDN blog post. As a release candidate nears, ahead of a possible 2009 launch, there is at least one improvement eco-minded admins and users can look forward to:

Locking a machine without a screensaver

It isn’t uncommon for IT administrators to want their corporate machines to auto-lock after a certain amount of time. In Beta, enabling this functionality required a screensaver to be set. We’ve since made a change to allow this functionality even when no screensaver is specified.

A nice little boost to security. And screensavers are notorious energy wasters anyway, although some are really neat to look at. You're better off letting the monitor go into power saving mode. Seriously, some monitors are works of art in and of themselves.