As previewed at MIX06... the IBlock beta is now availble for testing. And it is addictive. Unless you have a couple of hours spare playing with IBloks, then stay well away.
This is set to be one of the first commercial WPF apps. What IBloks does incredible well is show WPF's simple and clean integration of picture, audio, video text and 3D. I have decided to make an IBloks dancing man of myself, photographing my face and body parts and adding them to the man, and then making him dance... just need to find a digital camera... I will upload him once I am done! :)