I'm currently working on the handouts for my AU classes: two are sessions I delivered last year, so much of the work for those has been to go through make sure everything works on the latest product versions (and to update the screenshots, as they do look much nicer now that I'm running Vista, it has to be said :-).
As part of the update process for my "Enrich your DWF" session I've been looking at the new capabilities of the Project Freewheel API.
The best way to see the capabilities of the new Javascript API to Project 
Freewheel is to check out this page. I'll hopefully get more time to work on a client-side sample to show this working in the coming weeks, but in the meantime it's very interesting to note - in particular - the ability to receive events fired by changes to the current camera, path or section.
Hopefully, in time, we'll see the capabilities of the programming interface to Freewheel expand to approach those of the API to Autodesk Design Review, which has an event model providing information regarding selection (or simply hovering over) individual objects.
OK, now it's time to get cracking on the new material I'm preparing for AU, related to the use of F# inside AutoCAD...
