This week, a conversation with baritone William Stone. The newly appointed Temple University professor will, this weekend, lead students in a Kimmel Center performance of a work for which he has won a Grammy award. The Philadelphia Museum of Art moves ahead with its largest expansion ever. Susan Lewis has an update on progress. Jason Peifer watches the national production of Wicked load-in at the Academy of Music in Philadelphia. There's been a marked increase in incidents of major art theft in the past years.