Ive been playing random MMORPGS (Mostly Textbased) for the better part of the last 7 years. Right now I'm addicted to DragonRealms (
http://www.play.net/dr). IMHO, Its by far the best Textbased MMORPG that I have ever played. The community is awsome, and the RP oppitunities and sheer amount of actions you can preform are top notch. PvP is suported aslong as both players concent beforehand, If not then the offending player will become wanted within that provence. Its only downfall so far has been that the rate at which you gain experiance in specfic skils is directly related to your Intelegance Wisdome and Disciplin Stats. This is fine if you are play a character that you normaly would beef up these stats with (Like a mage or a cleric), but it seems to bring a bit of dificulty in later on with other professions if they neglect to advance these skills. Anyway, its got a 30day free trial thing happening at the moment so if you are interested in learning more, the best way would probably be to play it.
Hope this helps in some way!
-Keist