The SAG Awards nominee and author celebrates her new dating book in New York City. Plus: Patrick Dempsey, Britney Spears, Sienna Miller and more

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LEADING LADY

Sienna Miller (in a vintage dress) happily greets her public at the premiere of her movie Factory Girl Thursday at the Santa Barbara International Film Festival. Miller, who stars as 1960s It girl Edie Sedgwick, recently told PEOPLE that she felt her roller-coaster relationship with Jude Law had overshadowed her acting career. "People didn't want to pay attention to the fact that I actually took my work quite seriously," she said.