When it was CO, I got upgrades quite often as a Gold. Ever since the merger, that number has plummeted. Even as a 1K, it is hit or miss. I've failed on both a RPU (JFK-LAX) and GPU (EWR-LON) this year.
I've gotten CPU on a few routes to/from ORD this year. But the upgrade list is generally 20+ people so it isn't easy on the well traveled routes. Just look at how many are lined up in Boarding Group 1.