Reports are still coming in but it appears that (as this article says)
Peter was standing on a cornice at about 7,000-feet when the cornice broke or Peter fell through the cornice. Peter fell down the slope below and did not survive the accident. Peter may have died from the fall or may have been buried in an avalanche resulting from the cornice break and fall.
I've never been to Telluride and I've never met Peter but I've heard his name and know that he will be missed.