Matt - just FYI, if you didn't already know SP2 is out for Vista and Server 2008... so maybe you might want to try that?
(Betas - not RTM)

Here is some of the more important fixes they already have done

Adds new capabilities to Direct X Graphic display reliability. The graphics experience has been greatly improved for users, such as gamers, running applications that require a lot of graphics processing.

Adds support for the 64-bit central processing unit (CPU) from VIA Technologies, which adds the ID and vendor strings for the new VIA 64-bit CPU.

Improves audio and video performance for streaming high definition content.

SP2 also includes a Service Pack Clean-up tool (Compcln.exe) which helps restore the hard disk space by permanently deleting the previous versions of the files (RTM and SP1) that are being serviced by SP2. The Pack Clean up tool can also be run offline while creating slipstream images to reduce the size of the image.