well, I think I've just seen the future of computing.
kept reading about this kind of stuff but I'm still pretty blown away.
the service I just tested is called descktopondemand.com(domain's name is too long) and it gives you a virtual desktop that runs linux and gnome(I think it's fedora) in a window on your computer(you need to install a small program called nx desktop client, wich is available for windows, linux, mac and solaris).
they got everything you need(gimp, evolution, abiword, etc.) and it's blazing fast(works faster than my own computer running the same things...).
so the folks at google really don't need an OS to put on your PC. they can just give you a free cheapo computer that boots into something like this running on their servers and make their money off advertising.
it's not only possible, it's doable NOW.