I agree with what you said SPhilli911. Yes I am on 4K PS4 Pro, also noticed the Uncharted nods and the story draws you in around the 4-5 hour mark.
I am now very near the last mission but really do not understand the mixed 'Professional' reviews (4-7) The actual user reviews on MetaCritic are now up to a solid 8.0.
The Hordes are amazing and so far I keep avoiding them (if I can). Graphics and the amazing dynamic weather i.e hearing thunderstorms roll in (apart from a few pop ins and some frame rate issues) the details are great for such an interactive world. The skin and textures are one of the best if not better than GOW, Spidy and HZD as it has more natural lighting.
Before release I read quite a few details from Bend and they went for the 'Alive' humans and not 'Dead' Zombies and just 'infected freakers' that are hungry all the time and each one has his own dynamic world so will mostly come out at night but also they come out in the day to feed but yes it is a 'Zombie' Style Open World Game.
Overall I am also happy with the game and recommend to at least give it a go if you like HZD, Uncharted and Zombie games.