01/01/2012 11:24 am ET | Updated Mar 02, 2012

Justin Bieber & Carlos Santana, Lady Gaga, Cee Lo & More New Year's Eve 2012 Performances (VIDEO)

While you were pouring one out for 2011 and taking many in for 2012 with friends and family on Saturday night, New York City's Times Square and Hollywood were packed with star-studded performances.

From Justin Bieber's surprising "Let It Be" duet with Carlos Santana to Cee Lo's controversial "Imagine" performance to (and his head on many iPads) virtually singing "T.H.E. (The Hardest Thing)," the evening was full of surprising songs and dances to ring in the New Year.

Plus, watch Lady Gaga and New York City Mayor Michael Bloomberg countdown to 2012 and pucker up to each other.


New Year's Eve 2012 Music Performances