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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'SMASHING' PERFORMANCE

Rihanna jump-starts the Super Bowl weekend's festivities with a sexy (and star-studded) concert at the Ford Amphitheatre in Tampa, Fla., on Thursday. The pop star shared the bill at the Pepsi Smash event with Pete Wentz's band Fall Out Boy as Kim Kardashian (not pictured) cheered from the crowd.