I think i've read on here that it starts getting crowded around the 20th. Thats the day we leave so I'm hoping that when we go it wont be to bad also. And I've never been to disney that close to christmas but when you go it should be the christmas crowds.
Mickey's Very Merry Christmas Parade - it's a party at the MK that runs on scheduled nights throughout the holidays and for which you need to buy separtate tickets. It is a lot of fun (I hear!), with a parade, "snow" on Main street, shows, hot chocolate, picture taking, and the rides of course!