Still catching up, but as I've seen the question a couple of times...
I'm 99.999% sure that Sago Cay is currently being refurbished. DH and I were in one of the RPC honeymoon rooms (4203) from 11/29-12/2, and after watching all the activitiy outside of Sago, I think it's safe to say that there were NO guests staying there. The racket they were making late afternoon of our first day removing the patio furniture was enough to wake the dead, and you could tell at night by the lack of lights, how some of the drapes were hanging, etc., that it was uninhabited.
When we left the MK for the last time on 12/7, we noticed from the monorail that Sago had that "ghost hotel" look that others have commented on - they were obviously testing all the TV's, as they were all on, playing to empty, dark rooms.
We had an absolutely great time at the GF. My DH is now a believer (this was his 1st stay there). I'll report back with more details, but wanted to advise that Sago is definitely getting its makeover!