Traditionally, what dosraider said. Time with family, presents, dinner.
I've been moving in the direction of Mighty Midget, though. I'm not liking the whole buy buy buy fiasco any more. If there's anything I want, I can generally afford to buy it myself.
This year, my parents-in-laws are talking about pooling all our money into a big family trip sometime during the next year, which I think is much more in the Christmas spirit.
We wait until Christmas morning to open presents, making the children suffer, which is definitely fun for me!
Depending on where we go, it'll be lamb, or ham, for Christmas dinner on the 25th.