What turn based MMOG genre has more fans?

A fantasy RPG, a gangsters RPG/strategy game (like barafranca)or a war strategy game (like travian)?
Do you know of any popular turn based fantasy RPGs? I don't know of any, but I included it here because real time RPG is the most sucessfull genre.
I am a software developer interested in starting a hobbie project, but I would like it to be as commercial and popular as possible.
By the way I am also looking for a game designer (not paid), and I would be pleased if you joined me.

Thanks