Swift catches a case of the giggles during a TV appearance in Toronto. Plus: Gwen & Zuma, Rihanna, Nicole Richie and more

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LADY IN RED

Renée Zellweger braves the winter chill to make a sexy stop at The Late Show with David Letterman in New York City on Thursday. The actress chatted about her latest comedy, New in Town, which opens Jan. 30.