Scott Hanselman posted his notes and slides (and movies!) from his talk on the ASP.NET MVC framework, where he also mentioned and shows how he's write unit tests for the MVC framework in ASP.NET.
Scott has examples both in Moq and Rhino.Mocks on how to write these tests, so I created the parallel thing for Typemock Isolator. If you use Typemock Isolator and want to test ASP.NET MVC - you can go right here and use the MvcMockHelpers class.