Q: What is the definitive Christmas comic? — @Koltreg
A: "Definitive" is a pretty tricky requirement to meet. You have to find a comic that's not just definitively Christmas, with all that goes along with it, it has to be definitively comics, too --- and if you think it's difficult for people to agree on what Christmas is all about, just wait'll you try getting them to pin down one single issue that defines comic books as a medium. At least religion has centuries of scholarship; comics just has loudmouths writing columns about them on the Internet.
That said, I do think I've found one that's as close as we're going to get: 1989's Christmas With The Super-Heroes #2.