As an ArmA II fan and avid player since times before DayZ I have to say that DayZ is highly overrated, not because of being in alpha stages or for being highly glitchy(which is something that is inherit from ArmA II) but for being generally ... bad.
The concept is good but the gameplay and how it plays is not suited for that engine(ArmA II is highly flexible, but is orientated to shooting and ballistics simulation, not CQC situations like the ones featured on DayZ). DayZ heavily relies on cooperative gameplay, but is really hard to get into(Lacks a proper text bsed tutorial, or at least basic info on how some things work within the game, sure the lack of this info helps to create a more "exploratory" environment, but the most basic information in how basic stuff works is skipped for no apparent reason), most of the most basic features(like the inventory system) simply doesn't work, controls are even more complicated than the vanilla game (however this is mostly ArmA II normal layout, which is simple not suited for the kind of gameplay that DayZ is build for). The fact that people completely dismisses the vanilla game just to play it is also annoying, because as I conceive it the game itself (ArmA II: Combined Ops) it's pretty damn good for what it is, and is not just a base for DayZ. Other mods(ACE and I-44) have demonstrated even further potential than DayZ itself.
I'm still holding some hope that by playing DayZ with a group or clan might indeed improve the experience, but how I see is just a mod that overshadows the great game that ArmA II really is.