Commented video comparison of final PC version at ultra vs. Gameplay Trailer - Gamestar.de (German)
PC version is at maxium with 7490k + GTX 980 without day 1 patch
short Summary:
View distance is (way) worse
less/no Tesselation (Pause at 3:11, edge of wall for example)
way worse sky
lower LOD
low res textures in final PC build compared to trailer
Insinde buildings way worse lightning
worse water, again no tesselation
and ofc. way worse fire
The commentator says the final PC-version is a lot closer to the PS4 version then the trailers of 2014 and theres no way that could be changed with a day 1 patch.
Game looks still good, but nowhere near what has been advertised in the gameplay trailers, so in my opinion downgrade confirmed once an for all.
PS: i wonder how long this Video will be online, considering PCGH had to take down their video.
PPS: im german, so dont be rude if you find any typos or grammar errors