Broadly I like the unit test support in VS 2005 team editions. The integration with the IDE is sweet as are some of the features like test configurations, built in code coverage etc. Translating between NUnit tests and VS2005 unit tests is a fairly quick mental shift.
But where I do have more of a problem is that MsTest is not redistributable without the IDE. For the scenario of a build machine on which I want to install the .NET Framework SDK and build with MSBuild, I do not want the IDE installed on my build machine just to run my unit tests as part of the build process (we practice continuous integration). This can be a deal breaker.
This was raised during the beta process, in differing guises. The suggestion to use the Visual Studio Team Test Load Agent seems like overkill for this problem. That tool would seem to be about load testing, not about building software.
It would good if we did not have to wait until the Orcas time frame to get a solution to this one.