I was at the Canadian Open today for the practice rounds, the rough is nasty in the 6 to 8 inch variety. In the AM it was wet, and the players were struggling to get the ball to the green if they were more then 150 out, in the PM it dried up a bit and was slightly better. A member said "you know your rough is long when the grass goes to seed!" One of the members told me the PGA Tour was by to re-rate the track a few weeks ago and told them to not even bother to post their scores. I suspect there will be a lot of three woods, hybrids and irons off the tee, as you are better off with 200 yards in from the fairway, then 100 from the rough.
Should be fun!