Jane Pauley hosts this week's broadcast, which features Jim Axelrod's remembrance of the 50th anniversary of the assassination of Sen. Robert F. Kennedy. Also: Mo Rocca talks with former President Bill Clinton who has a new gig – co-authoring a thriller with novelist James Patterson; Lee Cowan visits Roadside America, a miniature town and model railroad extravaganza; Anthony Mason talks with musicians Stephen Stills and Judy Collins, whose breakup years ago hasn't precluded them from going on tour together, singing the songs of romance and heartbreak they'd inspired in each other; Serena Altschul checks out an exhibition of works by the post-war artist Jean Dubuffet; and Michelle Miller finds out why brightly-decorated pianos are turning up on New York City streets.