Damon earns top honors during a ceremony at Harvard University. Plus: William & Kate, Shakira, Courteney Cox & Lisa Kudrow and more

THE SING-OFF

Man of the hour Seth Rogen storms the stage as the Backstreet Boys – Kevin Richardson, AJ McLean and Brian Littrell – rock out during the actor's Hilarity for Charity event, which benefits the Alzheimer's Association, at the Avalon in Hollywood on Thursday.