Hi 9ers, I'm one of the dev's on the WPF graphics team.  As you can see we're really excited about 3.5 SP1.

We haven't figured out the mechanism yet (msdn, codeplex, blog, etc), but I plan to release the transition demo+source once 3.5 SP1 ships.  We understand that not everyone has experience writing pixel shaders, so samples like this (and others) will be worth looking at.

As David said in the video, the shader effects integrate really well with the WPF platform.  This mean you can take a library of effects, and just drop them into your XAML without knowing a thing about HLSL.