it could only work if it was open source and everyone that has an iphone on the mountain constantly updating live, so it would take a lot of dedication by the users, not the programmers. for example, once you ski a line you'l have to take your iphone out, find the line, then put in all the info from snow condiions to the difficulty.
actually, thee is another way to do it where you get all the resorts to put stuff they put on their website into the app every hour or something, but then It'll be easier to go to their website?
and besides, I don't think you'd get wifi on most mountains?
I dunno, it could work, but with a lot of dedication from both users and the mountains themselves.