Been playing it a lot this week. Combat is actually not like most MMOs. It's a little more twitched base. Although it's a bit subtle, it really does mirror 4E D&D in more than just name. People THINK it's a WoW clone, but classes really don't play that way. A Cleric is not a WoW healer, and a Guardian Fighter is not a WoW tank. If you try to play them that way, you will get fucked up. If you play your class the way you would in the pen and paper game, you'll probably do really well. Lucky for me, Cleric and Fighter were my most played classes.
My biggest criticism for the game is how limiting the classes are. They've taken the broad 4E classes and put them into very narrow scopes. In the pen and paper, Guardian and Great Weapon Fighter would both be the same class, and still would not represent even half of what the Fighter class is capable of. I'm not fond of their decision to make these different build options into completely different classes, but it does work for the game.
It's fun! Give it a chance. Get at least to level 30-35ish. Let yourself experience a wide array of powers.