John Mayer getting his hair cut at Sally Hershberger's salon in the meatpacking district ... Celine Dion getting into an SUV ... Chris Noth walking to the set of Sex and the City 2 ... Michael Douglas working out on a treadmill at the Equinox on 77th Street ... Naomi Watts walking to her apartment building in NoHo ... Ivanka Trump signing autographs after an appearance on Regis & Kelly ... Alessandra Ambrosio shopping with her daughter in the West Village ... Taylor Momsen talking on her cell phone while standing on the Gossip Girl set ... Hugh Jackman and wife Deborah Lee walking in SoHo ... Ed Westwick and Jessica Szohr arriving at Ed's apartment ... Tim McGraw getting out of an SUV ... Edie Falco shooting scenes for Nurse Jackie ... Usher walking outside ... Penelope Cruz leaving her hotel en route to JFK ... and Rihanna heading into a recording studio downtown.