Is this a Christmas Song? | Amanda & Matt

We LOVE this new song from Pentatonix, but is it a CHRISTMAS song?  The acapella group recently did a cover of Chris Tomlin's "Amazing Grace (My Chains Are Gone) and performed it LIVE for the Rockefeller Christmas Tree Lighting.  

It gave Amanda chills, Matt says but if this is a Christmas song...then all of our music is.  Will you help us decide?