Solution!  Service Pack 3.

Hey, I came across this problem again and was helped out on another thread.  Having service pack 3 solved the No OpenCL Devices Found problem.  I also needed .NET 2.0 (for catalyst) and python 3.2 for guiminer (solved the Application couldn't start, incorrect application information problem with guiminer).  (And I've done this from a scratch a few times so I'm fairly sure those are the minimum requirements on top of the catalyst drivers)