We were there yesterday, Nov. 7th, and the crowd level was low. Most rides were 5-10 min. Also, the Christmas decorations (including the Main St. tree-lit) are already starting to go up. The crowds level reminded me of the normal Oct/early Nov. crowds, before the Halloween change. (We were also there on Wed. Oct. 11th and 25th and both those days were busy. The 11th apparently falls on Arizona's fall break and there were a lot of AZ license plates in the parking structure)
Also, we had a unusually hot day yesterday (and for the few days preceding) and we even rode Grizzly Rapids (5 min. wait) with no ponchos-it was over 90 degrees!
I would recommend early Nov. next year (before the "official" Christmas start.)