I liked AoC, mainly because it seemed to be in keeping with the spirit of the original Conan books, atmospheric with loads of gore and grittiness and not just big breasted women, though I guess that could be a bonus too. The combat is not bad, but it's best to be in a group. You can expect a lot of deaths if you try to solo stuff, especially if you're just below the level of the quest/zone.
Think you need a decent PC for this game. The graphics in high settings are excellent and the musical score is probably the best I've come across for any MMO.
DCUO was a surprise. I'm not really a fan of the DC universe, but the game is good. The combat is actually very fast paced and dynamic. A lot of stuff can be happening at once and you need to have good reflexes/twitch skills. You can download it for free on the PC, but I installed it on the PS3 and the controller seems to work well for the combat. Sometimes, you don't lock onto the target you want or the camera is facing the wrong one, but it's a **** impressive MMO for a console game.