4/11: Landmark meeting between Obama, Castro in Panama; Democrats await Hillary Clinton's presidential announcement

President Obama and Cuban leader Raul Castro met on the sidelines of the Summit of the Americas. Their meeting marked the first substantive talks between a U.S. president and a Cuban leader since President Eisenhower was in office. Major Garrett reports; Hillary Clinton is planning to announce online that she will run for president again. CBS News elections director Anthony Salvanto shares what polls say about where she stands.