Today's hooray-for-Vista press release from Microsoft includes this quote from Autodesk:
"Autodesk has worked closely with Microsoft through the development of Windows Vista....Our internal tests give us confidence that Windows Vista will offer a highly stable and feature-complete platform that will bring our customers' 2-D and 3-D designs to life. Receiving RC1 is another important milestone on the way to making this happen, and we look forward to testing it."
So now you know: running Autodesk software on unstable and feature-incomplete versions of Windows (could that be 2000 and XP?) is making your 2-D and 3-D designs lifeless.