Rick Reitmaier is an engineer on the Flash Player team (formerly of the Flex team) and gave a talk at Stanford a few months ago about the virtual machine used by Flash Player 9 (AVM2). This is the stuff that we’ve contributed to the Tamarin project. The first 20 minutes or so are getting the folks in the room up to speed on Adobe/Flex, etc, but he begins getting deeper after that.
Check it out! ETA: (unfortunately this is Windows Media)