A lot of fun! Class based combat can lead to very dynamic fights. For $20 you can't ask for much more.
The movement and camera are very reminiscent of Unreal Tournament 2 (the one with melee weapons); wall jumping on to rooftops during heated battle is a beautiful thing considering positioning and line of sight are crucial here. With 5 classes to choose from there will be something that satisfies almost all play styles.
Some advice for new or potential players: Work as a team! Although having 2 shamans in the middle of a team which stays together is very effective, a coordinated counter attack by a team could easily break it up. It just seams a bit unbalanced as there are a lot of noobs and no ranking system yet. I'm confident that once these systems are in place, combat will be fun for players of all skill.
Final Thoughts: If you like Unreal Tournament or MMO-like PvP then go get this game and help bolster the community... we need you! Seriously, this is one of the best $20 I have ever spent on a game and has rekindled my interest in competitive multiplayer. I really like coop games so lone-wolf oriented games like CoD do not appeal to me. I tried the shaman for my first time last night and I played until about 2am (started at 9pm...).
See you on the battlefield!
PooPinPat