The developers on the standalone version of DayZ put out a blog post yesterday covering the current state of the game. It will be out on Steam Early Access soon, and the developers made it clear that "it's a true-blue alpha."
Many of the game's features won't be ready when it comes out on Early Access, and "Buying early will be a recipe for disappointment." This doesn't mean that the finished game will be bad, but anyone expecting to jump into a polished product could be surprised.
Early Access is really for people who want in on a game as it is being developed, and the DayZ team says that this is the opposite of what many gamers want. This Early Access version of DayZ will be targeted at "a core audience who want to get deeply involved in a very barebones experience that is a platform for future development."
Quick update for 4 December 2013 [DayZ Forums]
Valve updates Steam Early Access FAQ with warning that some games won't be released
7:00 AM on 06.06.2014