Jane Krakowski and Zachary Levi host the 77th annual lighting of the Christmas tree in Manhattan, which is illuminated by music artists rendering current hits and holiday tunes. Performers include Michael Bublé, Aretha Franklin, Alicia Keys, Barry Manilow, the Roots and Shakira. Appearing: newsman Brian Williams; and actors Taylor Schilling and James Tupper, both of "Mercy."