I was at WDW from Dec 3 -- 11th. We walked onto everything each day!!! I planned it right for which days to go to which parks. We were at the MK last Tuesday and I couldn't believe how light the crowds were. We had done 90% of the park by 1pm.
The only day which we felt and saw the crowds was on Saturday, December 10th. We were at EPCOT. The entire week, I only had to FP one ride, Soaring and it was on the 10th I did that.
Other than that, the crowds were very light. The cheerleaders were annoying (as well as their parents) as ever but didn't interfer at all with our vacation.
I was even surprised on December 3rd in the evening the MK wasn't as bad as I thought it would be. EEH weren't that great, we didn't stay long but it did start to rain that night too. (Dec 7th)
Thanks to everyone on the boards for the great advise.