— Monday's Scream 4 premiere in Hollywood brought out veterans like Courteney Cox, 46, David Arquette, 39, and Neve Campbell, 37, as well as fresh faces like Emma Roberts, 20, Lucy Hale, 21, and Hayden Panettiere, 21. Twenty-one-year-old Shenae Grimes — who appears in the film's opening scene — even posed with gothic rocker Marilyn Manson, 42, on the red carpet. [Pop Sugar]
— Emma Watson can empathize with Kate Middleton, 29. "Poor girl; that must be an incredible amount of pressure," Watson, 20, said of the future princess' televised nuptials. "I hope she's enjoying it. Must be intense." [Huffington Post]
— Rihanna, 23, Jennifer Lopez, 41, and the Black Eyed Peas have all been added to the list of musicians scheduled to perform at the 2011 Billboard Music Awards. Airing live on ABC on May 22, the event will take place at Las Vegas' famed MGM Grand Hotel & Casino. [PopEater]
— The Hangover's Zach Galifianakis has a few problems with technology. "It's making our society less private," the 41-year-old actor complains in GQ's May issue. "Like, I would advise people that while it's okay to tweet about your paper-towel purchase, I really don't want to know about what shape your stool is in." [Just Jared]
— The Harry Potter films will live on even after the eighth and final installment hits theaters this summer. According to producer David Barron, moviemaker Morgan Matthews shot a behind-the-scenes documentary during the final film. "He had incredible access to talent and crew and has made a documentary. . . that shows the challenges of making the film and the tolls it takes on actors and crew," Barron says. [Wonder Wall]
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