Hi Mark,
Ok so your thread on Sketchup has caught my attention. I dowloaded Sketchup 6.0 (31 mb) and installed same on my pc.
I then imported an AutoCAD 3D timber frame model and was pretty impressed by the apparent error free way in which this was achieved. I obtained immediate benefits in that previously saved "Views" made inside the CAD programme were saved by Sketchup and then used to provide views between which Sketchup will then annimate the model making transitions between the views. This software must provide huge benefits for customer review of 3D model drawings when they are neither computer literate nor wish to lay out mega bucks on a full blown CAD package. The dynamic shadowing facility is impressive.
I am not sure how the models can be copyright protected or secured from intellectual property data miners. Have you figued anything out yet in this respect.
Regards
Ken Hume
http://www.kfhume.freeserve.co.uk 
