Inarguably SL2 applications are a whole new experience of developing cross platform applications from managed code environments.
Unit Testing becomes very vital while developing for cross browser enterprise class applications. Visual Studio's tight integration of the Unit Testing framework is such an invaluable tool in the code production pipeline. Now, with the release of a unit testing framework for SL2 applications, the same experience can be leveraged. SL2 applications can be developed in a test driven fashion now. It perfectly suits an agile team. A team which is constantly driven by change and is delivering on a constant basis, almost every day in some cases. Much like a team which does not have a release model. (Check out Jeff Wilcox's blog). I guess the Silverlight test framework was itself developed using an agile methodology.
The SL Unit testing framework has proved to be an invaluable tool personally for me. It allows me to test SL applications on 3 different browsers (cheap guess if you are thinking which browsers ) even though i target IE mainly. :P. I'll write about it with a test application soon in my next blog. Till then, check out these links..
Silverlight Toolkit - You can find components like dockpanel, treeview etc for SL 2, themes and of course the source code for controls with unit tests and the unit test framework itself.
Jeff Wilcox - The guy who develops actively on the SL unit test framework at MS.
Scott Gu's small demo program on SL unit testing - (If you don't know this man, you are not worth living, jump off a building NOW!)
MS Silverlight Unit Test Framework - MS unit test framework for SL 2.