I recall reading on the forums recently that someone installed SP1 and could no longer see any of the test types in the New Test dialog. We could never repro this and honestly were at a loss for why that could occur.
Recently a fellow employee ran into this and I had an opportunty to debug the issue on their machine. What we found is that the template folder had all the right test templates, but the item template cache was missing many of them. The solution was to run "devenv.exe /setup".
We're still not sure how it gets into this state, but I'm happy to now know what is wrong and how to resolve it.
Engineering Lead, VS Team Test