They could pretty much cut and paste DayZ, revamp all the clunky UI elements and movement, fix all the glitches and bugs, and I'd buy it. Anything more than that is just gravy. DayZ is its own worst enemy, I'd say 3 out of 4 of my deaths are to bugs and glitches. Inventory management is a nightmare. Want to chop that zombie up? Too bad you have to drop that gun first put your hatchet on, RELOAD it, put it back on your belt, then pick it up your gun again. By that time your face is already eaten or the zombie lost interest. The War Z has a ton of potential, let's hope they don't screw it up.