One of the best things about Pittsburgh is the Pittsburgh Symphony Orchestra, which became the first American orchestra to perform at the Vatican yesterday in a program entitled the Papal Concert of Reconciliation. It was quite appropriate for a concert celebrating the 25th jubilee of John Paul II; in addition to the pope, the concert was attended by Emeritus Chief Rabbi Elio Toaff and Abdulawahab Hussein Gomaa, Imam of Rome's mosque.