In a bit of YakShaving today I found the need to modify the MSTestSummary.xsl file for CC.NET so that it worked properly with the output from mstest.exe 2008. I haven't seen if 2005 uses the same format or not.
Anyways, hope some find this useful. You can download it from my CodePlex site here. I'll see if ThoughtWorks wants to put it up on their site.