The singer takes center stage in N.Y.C. Plus: Mischa & Cisco, Ashton Kutcher and more

'BASIC' TRAINING

Christina Aguilera gives her regards to New York City during her Good Morning America concert Friday, where she sang her hit "Ain't No Other Man" and other songs off her Back to Basics album before a packed crowd of 5,000. Just a few days earlier she celebrated her CD's release around town.