I just wanted linux gamers on this forum to know that the NWAC demo runs fine on my OpenSuSE 12.1 laptop. I installed steam via Wine and then downloaded the NWAC demo "inside" steam. The game does not run perfectly, it has it's problems: No zooming with the mouse wheel, steam crashes if internet conection is lost (I use offline mode) and if you try to start more than 3 scenarios/tutorials/campains from the game menu without restarting the game it also crashes. Otherwise it runs almost flawlessly.
So there you have it, no reason not to try NWAC just because you are using linux