The Purple One signs off on a 21-concert tour in London. Plus: Lindsay Lohan, Jessica Alba and more

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IN TUNE

While girlfriend Jessica Simpson emceed a Pussycat Dolls concert, John Mayer took part in his own musical event: headlining the New Orleans Jazz & Heritage Festival on Saturday. The singer helped close out the festival's final weekend, which also featured performances by John Legend and Harry Connick Jr.