Fun game, the pvp is fast, but if both players are on their game the fights can be close. Level 30 players can be beaten by a couple of 10's if the lower guys coordinate well. The PvE side is very good, with comic style cinematics, full voice-over and well laid out city zones.
If you liked CoH or Champions Online I'd assume this will rub you right. There are still some unfinished game features and some rampant glitches, but no crashes so far.
Play on a PvP server or you might get bored though, half the fun is flying around looking for action.