It isn't. The Dark Souls 2 pre-release demos had actually better assets and a improved lighting engine.
Indeed.
Looking at the completely real-time TGS 2013 trailer (which is 1080p, 60fps and must be running on PC) one can see not just the dynamic lighting & shadows but some of the better assets as well. More geometry detail in breakable things (the pillars), many more particle effects. I haven't see a good texture comparison but textures apparently took at hit also.
http://www.gamersyde.com/hqstream_dark_souls_ii_tgs_trailer-30829_en.html
https://www.youtube.com/watch?v=vjZvXpOMGxY
None of these things were present in the vanilla PC version (nevermind PS3, 360) nor any version of SotFS including PC ver.