Ehhh, read a lot more :).
Its Arma II, remade into a Zombie
/Survival game.
You need: food, water, shelter(?), bandages, medicine, and weapons/armour and if your lucky, transport

.
So in fact, its very little like L4D as its survival not waves. A server full of people, One continent/Island, all out to survive the longest.
Btw, if you fall or your vehicle crashes, you do get hurt... which is really bad.