When trying to create a unit test in a test project, the “Create Unit Tests” screen shows no types, thus the wizard cannot continue.  The [OK] button is disabled, and the only thing the user can do is cancel the unit test wizard.  This happens on Visual Studio 2008 SP1 on x64 (for me).

Not sure why this is, but if you have a database project type [SQL Server 2005/2008], remove that project from the solution and the type window for the unit test wizard will now work and let you browse types in your project for test method creation.