Just downloaded the demo....
I really like it all in all. Few minor Fifa niggles which have existed for a while. Players still seem to skate/bob up and down on the pitch. The AI keep doing this thing where they run one way and if you follow them, they turn back on themselves in a 360 motion. Players also still seem to be on rails. There seems to be less freedom than there is on PES. AI is also light years behind PES.
With that out of the way, it's very good. Animations are amazing. Ball physics are top class. Shooting seems brilliant. Goalkeepers are very good. They've pretty much nailed nearly everything. Definitely a big improvement on 10 and 11 (which i didn't like that much).
The commentary is also top class.
I really like the new defending. I found it really easy to get the hang of as it's practically the same as the new defending system on PES. When i was reading about how people on here were struggling with it, to the point where they were turning it off i was a bit apprehensive about it. But having played it, i think it's pretty much perfect.
All in all, i'm buying it. Really impressed.