A few weeks ago Kevin Smith (UK MCS Service Line Architect) released the second version of BizUnit. BizUnit is a framework for the automation of functional and regression testing of BizTalk solutions. Just think of NUnit ;).
The .MSI can be downloaded here: http://workspaces.gotdotnet.com/bizunit
It has a number of enhancements over the previous version that you can read about here: http://blogs.msdn.com/kevinsmi/archive/2005/07/17/439728.aspx.
BizUnit can be used in conjunction with Jason Births ‘Orchestration Profiler’ to ensure that a solution has an adequate level of test coverage allowing it to be deployed with confidence. The Orchestration Profiler can be downloaded here: http://workspaces.gotdotnet.com/orchprof
Unfortunately I still haven’t had the time to look at this and to try it out before using it in a project situation. It’s high on my ‘try before you die’-list though.