At last night's Memphis .Net users group meeting, Mark Mydland from Microsoft talked about the up and coming enhancements to the testing portion of the next version of Visual Studio Team System. One of the new features that I liked was the ability to record a test sequence.

Another topic discussed was PEX.  It is a new product from Microsoft Research.  From the web page:

Right from the code editor, Pex finds interesting input-output values of your methods, which you can save as a small test suite with high code coverage. Pex performs a systematic analysis, hunting for boundary conditions, exceptions and assertion failures, which you can debug right away.