I've been playing this game since closed beta and have been having a blast!
I'm a huge fan of the ARPG genre and this game by far has everything I ever wanted in an ARPG. It has a huge open public world where you fight along side other players making the game even more dynamic. The game right now consist of 21 heroes (5 more will be released soon) that is more "classes" than any of the other ARPGs that has come out in recent years combined; giving this game an insane amount of replay value. Brevik mentions that their goal is to add new heroes hopefully at the pace of LoL, and they will continue to improve the game with constant updates for years to come.
Also, the endgame has a lot of potential right now even in its infancy you start out with daily missions and working your way up to group missions which are normally called "raids" in other mmo's. I'm looking forward to seeing what Brevik and company will come out with in the future.
Everything that I've written about is just the tip of the iceberg and not to mention this game is f2p! You can't beat that. So what are you waiting for? If you're an ARPG fan like I am I am pretty sure you'll find some kind of enjoyment out of this game. And even if your're not into ARPGs, it doesn't hurt to give this game a go. All it takes is a little bit of your time and you'll never know; you might be surprise on how good it is.