Sir Paul McCartney, The Cast Of Sing, Jimmy Fallon, And The Roots Sing “Wonderful Christmastime”

If you put together a list of the top Christmas songs from the last few decades you would have to include Paul McCartney and Wing's "Wonderful Christmastime".  Sir Paul, and the cast of the new movie "Sing" recently stopped by The Tonight Show with Jimmy Fallon to do a really cool a cappella version of the song.  Check it out: