Twenty-five years after their first hit record, Coldplay's current world tour, which Billboard calls "the biggest rock tour of all time," has earned more than a billion dollars and sold more than 10 million tickets. During a stop in Dublin, correspondent Anthony Mason catches up with Chris Martin, Will Champion, Guy Berryman and Jonny Buckland to talk about "Moon Music" (the band's tenth studio album), the songwriting process, and their future playing together.