No, we're not announcing anything called JMAX today. Although if we were, I wonder what it would stand for? The graphic is meant to imply a "behind the scenes" look at XAML. You can probably tell that I'm not a designer. 🙂
Tim Sneath has an excellent one-hour interview with Rob Relyea up on Channel 9. Rob talks about the history of XAML, how it's been designed, how it works, what a BAML file is and what's in it, how the build process works, thoughts on debugging, tooling, and much more. If you've ever wanted to know how XAML ends up being used in your WPF application, this is a great interview to watch. Plus, it's part of Channel 9's Going Deep series, which means that it's chock full of juicy technical bits. And don't forget that Ctrl+Shift+G in Windows Media Player will speed up playback, so you can get more information in less time.
If you're just learning WPF or consider yourself a beginner, the XAML Overview page in the Windows SDK is probably a better place to start.