I hope I'm wrong...but expect higher crowds than you read!! We went the same time this past year (left day after Thanksgiving and stayed til Wednesday Dec. 4th) and it was WAY busier than they predicted! Beings Thanksgiving is so late, it makes the first week of December busy!
We were expecting 4's...and Magic Kingdom was wall to wall people. We spent two "days" at MK...the Sunday and Wednesday. Nights were way better! Now, don't get me wrong, we were able to do almost everything we wanted! But it was still busy! My DH kept saying, "You said it was suppose to be a 4!!" I know others there at that time thought the same thing...that crowds were way heavier than was predicted!! I thought it felt worse than summer crowds!
Like I said, Hopefully I'm wrong....Good luck!