I just happened upon a video put together by Jason Dolinger on the WPF MVVM (Model View ViewModel) pattern, which I found to be excellent. In this 1.5 hour video he refactors a simple application using the pattern and does a great job describing the benefits as he goes along. It is also interesting to see his use of Unity as well. Here is a direct link to the video:
http://www.lab49.com/files/videos/Jason%20Dolinger%20MVVM.wmv
And here’s a link to a blog post about it with a link to the source code:
Enjoy!