Hmm, I'm always looking for newer Christmas songs, or the more unheard ones that you likely don't think of Christmas so much when hearing them. I like all the usual stuff too.
Here's some less heard ones, or at least not old classic versions:
Amy Grant - I Need a Silent Night
Carol of the Bells ... from, uh Home Alone.
Charlotte Church - O Holy Night
Coldplay - Christmas Lights & Have Yourself A Merry Little Christmas
Enya - One Toy Soldier
Faith Hill - Where Are You Christmas
Jack's Mannequin - The Lights and Buzz
Jan Arden - Make it Christmas Day
Jewel - Hands (Christmas Version)
Jose Mari Chan - Christmas In Our Hearts
Loreena McKennitt - The Holly And the Ivy
Nana Mouskouri - Old Toy Trains
Relient K - Sleigh Ride
Rob Thomas - A New York City Christmas
Sarah McLachlan - River
Selah - Light of the Stable
U2 - Christmas (Baby Please Come Home)
Anyway, I hope everyone has a Merry Christmas.