The demo is a lot of fun. I preordered for PC.
The thing that sucks is the ‘matchmaking’ system they implemented. People on steam forums are up in flames about it. A server browser exists for the game but dedicated servers default to not allowing you to join a server through the browser. I’m sure they will fix all of that.
Gameplay is nuts and awesome. The demo is only 2 pieces of a map but its definitely got the dynamics of never knowing when the zombies will attack goin for it. The weapons feel good for a zombie game and friendly fire really makes you ‘think’ before you shoot.
I had to learn to use the melee (right mouse button) well. It is a quick swing and can really save your *edited*. Currently (this may be a bug) but you can hit R for reload and then do a melee attack and your weapon is reloaded by the time the attack is done. Currently it saves my *edited* but I don’t know if that is intended 
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Just my initial reaction.
Oh, and the TANK hurts bad 
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