As I recall they had a very basic wet shader in 1.0, I remember when it rained my hair would get darker and would look wetter as a result. I'd be surprised if they'd have tesselation on release, I mean the game has to run well on PS3 too and so far as I know PS3 doesn't support that. They may one day release an official graphics upgrade specifically for the PC version (like Bethesda has done with Skyrim), but I sincerely doubt that would take priority over new content.
