Here is a WSJ article about the origins of Irving Berlin's White Christmas. The writer goes into the details of the creation, history, and text-setting. My favorite quote:
While others might have stressed "dreaming" and "Christmas," for example, "Berlin deftly emphasizes the seemingly unimportant 'I'm' with a whole note, then races over the other syllables" before the next whole note, "white."
Yes, we get it. There's a subliminal subtext: you're white.
But seriously, a couple of my recent favorite Christmas tunes are The Waitresses's Christmas Wrapping (it came out the year I was born) and this new one that was released a couple years ago:
Anything with a Mariachi tidbit makes me happy.