I am completly against a CT MMORPG, for a few reasons.
One, it would completly change the series, for the worse. Sure, it would probably be immesnly popular and picked up by tons of people who know nothing about the series if the mechanics were right (Diablo II and WoW sold like hotcakes, if you didn't get that memo), but honestly I don't want that.
Plus, if you didn't notice, MMORPG's lack something that console RPG's have: a STORY. There's character development, sure, but it's all in terms of upgrading your strength and spell's, and nothing to do with personality.
In all honesty, a CT MMORPG is a horrible idea in every aspect. Diablo II was fun (I played it for a good 1.5-2 years in 8th-9th grade, I'm now a Jnr in college) because it was mindless clicking, and no story to get logged down with. You don't want either of those thigns hapenning in a Chrono game.