The attention put into the terrain and elevation, how trees look actually old and forests pull you in and the animation of the wildlife in reaction to the nature around , when i lets say play AC origins/oddessy i just get a fake and bored sense from the world around me.
So yeah i call that kind of attention for the open world unseen and in this case new and innovating because it adds so much small things to make it feel more alive
The attention to detail is indeed great. I haven't noticed any interaction between animals though. They react to me, yet I haven't seen any animals hunt other animals. Far Cry for example has done that better. Corpses decaying, that's actually new I think. I don't think I've seen that before in games. However I never noticed that in game, stuff simply disappears when you go too far away and leave new stuff behind. Unlike Skyrim that remembers every thing you disrupt or knock over. (Hence the ps3 grinding to a halt if you made too much mess in the world)
As for God of War back on topic, I really liked the way it exposed more of the world to explore. Freedom with a sense of progression, an interesting way to re-visit areas. Just as you think you have seen it all, here you go, enjoy, you're not even half way done :)