I have played DayZ and WarZ for many, many, many hours. It hits home besides MnB Style gaming.
WarZ at this point is better.
WarZ isn't as arcad-y as some people may suggest.
DayZ zombies and map had quite a bit of bugs due to the fact of hard coded ARMA II.
DayZ this time around will be a standalone.
The major factor (IMO) that sways people from DayZ and WarZ is the zombies.
WarZ zombies walk and trot a little with rag doll effects, that actually die from melee attacks. (but only to the head of course.)
DayZ zombies run like Olympic athletes, hard coded I believe, and melee-ing them meant 50% of the time you die.
Zombies in DayZ spot you even when you're prone, super far away.
WarZ allows for quite a closer engagement. (Easier to sneak around.)
WarZ allows for a stronghold server that will allow you to build fortifications or farm food. Zombies will be on this server, the map will be smaller, if you want people to join you can let them. (these maps do not spawn weapons or anything that would make it so you can farm top tier equipment.)
Hacks are in every game. Deal with it.
WarZ has very active devs.
WarZ will offer "events," missions, and NPC's.
The map is fucking big just not as big as DayZ's.
WarZ's landscape and graphics are great! (Landscapes based on actual places. First map, Colorado. Not quite sure of the following maps although I did hear the next was going to be New York, but they aren't even finished with the first map.)
WarZ is less buggy overall.
WarZ move speed is pretty slow, and you have stamina for sprinting. (Remember this is alpha-beta.)
There are many differences, but truly you can't even compare at this point, because to my knowledge DayZ isn't even in standalone alpha yet, and WarZ's beta was just released.
At this point. WarZ is a much easier game to enjoy.
Also to clear up some chatter, in WarZ when you have currency or real cash monies, you CANNOT buy anything that makes your game easier. You can only buy visual effects (masks, flares, chem lights) and melee weapons, but again this is alpha-beta and the final release may be different.
Honestly, the game is fucking great, just try it out.
Also, don't trust anybody ever. Be very cautious. xD