I have this. So far the big changes are in the inventory...
Tab to get into it, start with only 4 inventory slots you can gain more by changing clothes i.e. Cargo pants give you 6 more inventory slots, hoodie sweatshirts give you 4, then there are tactical vests and backpacks to give you more than that. If you cant seem to target that item, just tab and there is a "Vicinity" section that you can click and drag it to your inventory.
Possibility of eating rotten food, getting sick and dying. Food and water is very hard to come by, died of dehydration/starvation twice last night. Rumors of getting sick from well water as well, may have to boil it first. Rumor also that soda relieves some thirst but may worsen dehydration which may be a hidden stat. Food and water also last through more than one use based on a percentage. i.e. you open a can of sardines and have 100% first bite takes it to 75%, then second bite to 50% and so on. Not sure if each bite relieves hunger or if you still need the whole can.
Very few zombies right now, literally ran full speed through Cherno and had may 5 zombies on me.
About 99% of buildings can be entered now, which I love. In the hours I have played I have come across one rifle and no ammo. Seems much harder to find.
Altogether I enjoyed the play, it still has a lot of work but it is DayZ. It took me about 45 minutes to get use to controls and figure out a few things but most controls are still the same. Let me know if you guys play it, I will jump on with you.
Also Steam makes joining someones server easy if they are on your friends list, just "join game" and it takes you to their server... you still have to find each other though.