Its a third person skill based PvP game. People say it is sort of like WoW PvP but pure skill based and fast paced. There is no auto lock and no items so all of your abilities must be timed exactly. You can play 1v1 up to 5v5, and the games are short so you get a lot of them in.
I've played it a few times the past few days and I must say that I can see this game being really fun once you get over the learning curve. You can download it and play 4 out of 16 or so characters for free. The 4 you get for free rotate on a weekly basis so you can keep trying new characters. To unlock the rest you can either pay for them or save up in game points to get them one by one.