Jay, I would not install Vista straight away.
I have a quadcore PC with a 9600gt nvidia and 8gigs of ram, and to be honest, Vista is never as stable online as XP was.
Also like it or not the NC10 is built around XP Service Pack 3. Which is the most common and one of the best OS available IMHO.
Do what you want but you should see how happy you are with XP first. Don’t forget installing more ram and the Vista cripples your warrenty.
I would seriously take my advice on this and wait and see how you like XP and what the machine is designed for. 😉