I was there around that time last year. I don't know if its more crowded the first day of the Xmas shows but it was manageable when we were there. It was crowded but my kids rode all the rides they wanted. I don't think they waited more than 15 minutes for manga. The penguins line was long at times but nothing I would have considered long. I think I have waited in grocery lines longer!
Xmas there? Awesome!!!! It was the best thing we did. All of my family thought it was fantastic. We walked on polar express. It was so magical! If you haven't been during that season before....just wait.
We ate at the shark restaurant..I made reservations the night before and the lady found me one.
Have a great time!