It is a fun time waster, but the developer is majorly shady and the promised expansions only revolve around a quick way to make a buck. Don't forget that the game is overrun with hackers. People are using ESP, aimbots, wall hacks, and a host of other things that make it downright unfair for anyone not using a cheat.
I have moved on for the most part while we wait for the Day Z stand alone. If Day Z keeps the crap UI from Arma then I am going to be done with the zombie MMO's in their entirety.