Which upcoming MMORPG should I consider joining?

I was all hyped up for Champions Online, which looks like an upgraded version of City of Heroes. But then randomly browsing for any new CO updates, I found the trailers for Mortal Online which looks FUCKING AWESOME (sorry for the language). Now I’m afraid to commit to either because I’ve realised how little I know about MMORPGs :P I’ve never played them (apart from a couple of months 5 years ago in Runescape). I want to join an MMORPG that:
– Is new. I want to see good graphics and have a chance to be ahead of the curve.
– Is fantasy-orientated. CO technically counts because you’ve got superpowers, but I’m not interested in EVE or Star Trek Online.
– Has a good chance of being a success. It would SUCK for me to invest in a game that is going to be a flop; MMO’s NEED to have lots of people on it to be a success.
If you know much about MMO’s and are keeping your finger on the video-game pulse, then please share your opinions.
P.S. Obviously I’m a PC user and I am prepared to shell out for a subscription and DVD-ROMs. None of this soft-core free click-and-play MMO stuff :P