There are some people playing it on a MacBook with XP on it, but I don't think that anyone has tried with Vista yet.  I can tell you that the people running on macbooks were having issues with overheating, so you will probably want to get a Targus Chillmat or some other external cooling device if you go this route.  In the same thread, other users were of the opinion that even though it's running XP, there are still compatibility issues because the BIOS is meant for Mac.    I can't find the link right now because the watch list filter is disabled.