Couples Watch: J.Lo & Marc, Gwen & Gavin ...

Plus: Calista & Harrison, and all the latest scoop on star romance

Photo: Bryan Bedder/Getty

• Jennifer Lopez, dancing like one of Marc Anthony‘s biggest fans during her husband’s concert at Hard Rock Live in Hollywood, Fla. “[She] had a wonderful time dancing to his tunes and wowing the people around her,” says a source, who added that Lopez “looked hot in a sequined party dress. And didn’t miss a beat!” (Lopez also sang four songs during Anthony’s rehearsal but never performed with him during the show.) After the concert, the couple spent the night in a room at the Seminole Hard Rock Hotel & Casino.

• Gwen Stefani also played No. 1 Fan: She checked out hubby Gavin Rossdale‘s Grammy/T-Mobile Sidekick concert at the Hollywood Palladium from a VIP balcony. Joined by No Doubt bandmate Tony Kanal, the singer sang, danced and even snapped pictures on her cell. Afterward, Rossdale met his wife in VIP and the two watched the beginning of Leona Lewis‘ set together.

• Newly engaged Calista Flockhart and Harrison Ford spent a day at the Smithsonian’s National Zoo in Washington, D.C., with son Liam. The group got up close and personal with Happy, a 5,00-lb. hippopotamus, which they fed, before checking out the giant panda exhibit together.

• Carmen Electra and fiancé Rob Patterson went shoe shopping together in New York’s Lower East Side. The duo stopped into Upper Echelon Shoes, where Electra nabbed a pair of black leather and gold-studded Chuck Buckle’s.

• Megan Fox and Brian Austin Green had a “quiet and relaxed” dinner together on Sushi Roku Santa Monica’s patio. Also there that night, Ben Roethlisberger (of the Pittsburgh Steelers) and Reaper star Missy Peregrym shared a romantic meal overlooking the ocean.

• By ANDREA DESIMONE, JENNIFER GARCIA, MARISA LAUDADIO and LINDA MARX

Friday’s Caught in the Act >