Pope Benedict XVI today announced in Rome that Boston Archbishop Sean P. O'Malley will be made a cardinal of the Roman Catholic Church in a ceremony at the Vatican late next month. O'Malley is among 15 new cardinals included in the first set of appointments by Benedict. The new cardinals -- who will receive the red hats, or birettas, that signal the rank at a ceremony in Rome March 24 -- will help oversee the Vatican's bureaucracy through service on oversight committees, and ultimately many of them could have a vote in the selection of Benedict's successor.