https://www.youtube.com/watch?v=yLkjgQ5XXPw   Lady Gaga & Tony Bennett headlined NBC's Annual "Christmas in Rockefeller Center" on Wednesday, December 3rd from 8-9pm ET.   NBC's Annual "Christmas in the Rockefeller Center" celebrates the music of the holidays. Lady Gaga & Tony Bennett, Cyndi Lauper, Seth MacFarlane featuring Sara Bareilles, Idina Menzel, Pentatonix, LeAnn Rimes and Trisha Yearwood are all set to perform.   “Today†show anchors Matt Lauer, Savannah Guthrie