I'm watching/listening at work through the Golf Channel website, I assume its the NBC/Golf Channel feed. I heard a discussion during the morning rounds that the lead group was "on the clock" at some point early in the back nine. I'm really only half listening, so I can't tell you the details, but there's at least some monitoring of the pace of play.
I wanted to get this PVC one and a skytrac to go along with it: http://allsports-us.com/collections/golf-cages
But I have a small back yard and didn't do so as to help insure domestic tranquility (with my wife).