Jamie Cansdale has just released TestDriven.NET 2.0 RTM. TD.NET is a great application to integrate all the main xUnit frameworks (such as MbUnit and NUnit) into Visual Studio 2005.
http://weblogs.asp.net/nunitaddin/archive/2006/10/30/TestDriven.NET-2.0.aspx
Definitely worth a download if you use TDD.