yup, thats exactly how it looks in my game too. just a pure white pixelated void of a texture...
Hmm, it appears to be the same in this video: http://www.youtube.com/watch?v=OFeWBzxPZX0
If you don't focus on it, then you don't really notice it out in the wild...but once you're in a cave filled with snow, oh the horror......

bliviongate:
It isn't so much as an issue, lastwolf, as it is incredibly ugly and bothersome to the eyes. Only when I'm in a snowy cave though, outside if I don't focus I don't notice. Do me a favor and load it up on the 360, head north to a snowy area and look closely at a rock. Does it look like a bird had diarrhea all over it? Honest question, if it doesn't, it doesn't. Just doesn't make sense to me.