I actually considered posting a DayZ thread on the weekend.... but I was way too busy playing. Literally haven't touched any other game for a week, all I play is DayZ currently.
Can't recommend this enough if you're a fan of survival horror or zombie games. The tension in DayZ is incredible compared to anything else out there. Crawling through a field of zombies at night, trying to get to the barn/building/whatever on the other side is nerve wracking. The zombies moan, gurgle and growl when nearby and it adds to the atmosphere immensely. Combine this with the fact that a bandit (PKer essentially) could be watching your progress across the field and is just waiting for you to get the loot and cap you on the way out makes it worse. It creates a great conundrum, if you use light at night, you let everyone around you know where you are. If you don't, you can't really see and risk bumping into a zombie and ending up in a world of pain.
Of course you can play in daylight, but it's not practical for a lot of people as servers run real time, so if you're like me and game at night, it will be night on the server also.
Running into other survivors can be epic as well, you're never sure if you can trust them (made worse by the new patch as you no longer change skins if you PK), so for me I usually avoid other people altogether unless I know who they are. If I can't avoid them, I make sure I'm the first with a gun on them and basically make it plain if you go your way, I'll go mine. Haven't had to murder anyone yet, but I have had a few fire fights with bandits. Won some and lost some.
And to throw a DayZ story in here for the fun of it. One of my more helpful moments in the game was when I was flanking around a city (Elektro if you're curious) through the forest, basically looking to detour round it. At one point I saw some poor survivor running down the road on the outskirts with about 10 zombies chasing him. He managed to get inside a small building and clearly ran out of ammo trying to drop the zombies. At this point I was ~500m away from his location, so wanting to try out my new sniper rifle I found (a CZ), I set up and began picking off the zombies (they tend to crowd around trying to get inside). A couple of missed shots later I was sighted in and dropping them. Unfortunately for me, other zombies heard my rather loud gunshots and began charging at me. I switched out to the trusty Makarov pistol and took them down, getting a little banged up in the process. Worried about the other survivor I quickly returned to taking out the remaining zombies. It was incredibly satisfying to see the other player slowly creep back out of the hut, wondering who the hell his guardian angel was, then take off looking for ammo. I then bandaged myself up and left on my way. Never said a word to him, found it more fun to give him a long range hand and move on. Just happened to be in the right place at the right time.
PS. I threw that sniper rifle away in favour of something quieter. Fire that thing in a town and you get a horde coming down on your head. For the newbies out there, never fire a Lee Enfield in town. Most people have died once to that.