Discovering XAML and XBAP

Ok, I pride myself with knowing alot about internet technologies. I've played with SVG, DHTML, canvas, flash, and a ton of derivative technologies that never go very far. But I have been completely in the dark with XAML and XBAP. I guess since you have to have some runtime or download Vista that I've never even seen demos of what you can do with this stuff. However, I just grabbed the Windows Presentation Foundation libs for my windows XP and looked at a few demos. What's insane is I discovered this while idly looking over at the WildTangent forums hearing that their web driver has been nuked.

I am floored! This is like a Flash/PDF/Widgets/Java killer app all rolled into one. I've seen 3D demos, documents like PDF, games, and tons of stuff. I still don't know how it all works, but it seems to be partially available via just XAML and some scripting. I can see now why Opera and other folks are doing the widget thing big time. If XBAP takes off in a big way - there's going to be some major competition for things like Flash and Laszlo. It's never been a better time to be an HTML/XML person with scripting skills.

Anyone out there know where to start with all this XBAP stuff? I feel like I've entered the theater after the movie's already halfway in....