I can't really see the problem in those pics.
They just look like boards covered in snow to me. Maybe the pics aren't high res enough for me to see.
Well anyone who has played Skyrim can infer that the textures are supposed to represent snow covered surfaces. The problem is that there is obviously no appropriate bump-mapping/lighting present on these textures, thus the snow looks more like flat, non-reflective white paint more than actual snow.
Personally, I have a feeling this is a byproduct of Bethesda's dynamic weather engine, along with the texture problems seen on snow covered rocks. If such is the case, it may prove to be very difficult to fix these snow issues as they may be directly intertwined with the engine itself.
Nonetheless, I am embracing myself for a witty "working as designed" comment from Bethesda about this.