Kilborn Stays Up 'Late' for Last Time LOS ANGELES - Craig Kilborn bid farewell to viewers of CBS' "Late Late Show" on Friday, concluding five seasons as its host despite the program's expanding audience.    Since announcing two weeks ago that he was leaving, the 42-year-old Kilborn has had difficulty explaining why he is walking away from a show that has seen its audience grow by more than a third during his tenure...