Jon,
Interestingly enough (and I'm hardly a big fan of XP), the leaned-down version of the OS (made with nLite) takes up about half a gig lesson the Eee than the bespoke Xubuntu version. I suspect that I could do something about that if I was willing to kill off the Linux swap partition (there is page after page on the Eee forums about tweaking this sort of thing). But the Xubuntu is snappier in most respects, even if it won't recognize the USB camera.
I do have AvoCADo bookmarked...I'll check it out again.
You are correct about SU on Linux...I spoke with people in Boulder about it and they said they didn't have the manpower. I would actually like to see a Google Docs online CAD/modeler one day, though! I already use the other Docs applications regularly.
Getting back to the Eee, though, I am finding that it is a nice little platform for coding...Java, in my case. using the Processing extension. I can sit at any table and just hack away, with wireless and the open-source media player VLC supplying the streaming industrial rock...and caffeine the inspiration. Perhaps the Java coding stuff will lead to something. Art of Illusion is entirely written in Java and has some nice capabilities.