First Things has a interesting post Looking for Mary in Christmas Carols By Michael Linton where he references just how few Christmas carols actually reference Mary.
It is hard to imagine a Christmas Crèche without Mary, but I guess most carols written since the Protestant reformation have done so.
Though this is not just a Protestant divide and something that effects just carols. Think of all the modern hymns that have unfortunately become standards in so many Catholic churches. I can think of only one one: Hail Mary: Gentle Woman. While the lyrics are okay I find the melody to be rather droning and when compared to some of the magnificent hymns for Mary, it is severely lacking. Funny with all the talk about inclusive language in the liturgy there has been no outcry against the lack of Marian hymns at most modern Masses.