I really love Marvel Heroes!
The Incredible Advantures of Van Helsing is new and pretty cool. It's not F2P though but it is cheap.
Legends of Dawn is also new. It looks like an ARPG but I'm not quite sure.
I liked Path of Exile but with all the hype it gets, it honestly ticks me off and makes me like it less. It is not better than Diablo 3 in my opinion, and that's what really makes me mad. People are ridiculous with their insinuations. Diablo 3 is a much better quality game than PoE, PoE just has a deeper leveling system. That's cool and all, but I'm just sick of people acting like dumbasses over it.
Drakensang Online is pretty impressive for a browser game.
There was also Fortune Online but I think that was getting shut down if it's not already, I forget; maybe not.
Torchlight 2 is excellent. Won my copy from MMO Attack. =)