I was there last year on Thanksgiving day. It was VERY crowded, but manageable. We got there at opening and stayed until 1. We did what we wanted in Fantasyland and then hit some of the other areas. If you get there at opening and utilize fast pass, you can get quite a bit done. We left at 1 to eat at Goofy's Kitchen. I was suprised that it wasn't crowded at all there. Then we went back to the hotel for a good Thanksgiving nap. We came back at 5 and did a couple of shows and then hit the parade and fireworks. That was the most crowded! Sit very very early if you want a good seat. I'd suggest 2 to 2 1/2 hours early. They added a 3rd showing of Fantasmic at 11:30, so we went to that too. It was crowded at the last showing, but not sardine like.... Good luck and have fun!