I have to say my favorite line out of the whole episode was the one where Jack comments on Zach's robot, and makes the priceless Firefly reference. Seeing Angela in an elf costume was absolutely hillarious as was the revelation that she photocopied her butt at the holiday party the previous year.
I loved the holographic Christmas tree, the secret Santa gifts and the idea that the crew had to deck the halls with lots of nothing. One of the the best parts of the episode was seeing the look on Ivy Gillespie's face when she say the tickets Lionel had purchased for them to go to Paris. And the part at the end where we see Booth with his son was just sweet. The crowning moment was when Brennan finally opens the gift from her parents and we see her smiling through tears. I was kind of disappointed that I didn't get to see what the gift was, but maybe it's better that way.