I think the MMO world is going to change here soon.
In the near future I'm sure we well see a FPS movement among companies. I say this because how many MMORPG's have crashed and burned to WOW and EQ?

You can all ready see it happening with Hellsgate, Huxley and others. The MMOFPS is still a new concept in production. The only reason why we see companies trying to come out with MMORPGs instead of MMOFPS, is because they are worried that players well get board of it fast, and treat it like a normal DM FPS game.