Read original post by Jeremy Likness at C#er : IMage
In the last post, I walked through creating a portable assembly that will target Silverlight 4.0 and above, .NET Framework 4.5, and Windows 8 Metro. In the assembly were a few classes that handled commands and property change notification for a simple view model. In this post I’ll show you how to reference the assembly in Silverlight and WPF and explain why it works.