I don't think an MMORPG would work as well on console, as from my experience Consoles don't have as much of a sense of community as on the PC, and community is, I think, one of the largest draw cards of an MMORPG. Communication is also a bit of a problem, as MMORPG's don't work very well without communication, and unless keyboards or Headsets become more widespread on consoles they won't work that well.
That said, I don't play consoles as much as the PC, so please feel free to disagree.