The DayZ style freewheeling gameplay has been in OFP/ArmA for 10 years. Sure, we weren't playing with zombies but large scale military missions that involved running around, hit and running AI and "living off the land". DayZ without zombies. I have no expectations that they're make any real improvements to the engine. Nothing has changed over the years except incremental updates to the graphics engine. The current DayZ gameplay has been possible since 2001.