Rose Bowl is Jan 1. Last year it was Jan 2 because there is some rule that says it can't be on a Sunday.
Anyway. That week usually is busy at Disneyland. All the holiday decorations are still up and schools are still out for their winter break. They last few years there have been ceremonies in the park for one or both teams playing in the bowl game. Plus many visitors who come for the game add on some days at Disneyland.
Now, it's not overwhelming crowds, but it is busy. New Year's Eve however is a zoo.
I've been there the week between Christmas and New Year's and it's been crazy. Some schools will have the week after New Year's off and some go back the day after New Year's.
This is good to know. I hope they give out the AP rates for the DL hotel. I also hope that the crowds will not be out of control like the summer months are.