Ask MIcrosoft. [EDIT] Ops, I forgot Nokia also sells Windows 8 devices. You may ask them too, of course [/EDIT]
try some real OS like Nemo, MeeGo, Ubuntu and if you are not satisfied with these OS's then try Android.
amaizing answers guis to a good questions.
I do hope so, to be honest. I'd love another OS to be experimented on the N900 as well.