Roger Birnbaum steps down as co-chairman, co-CEO of MGM;
Roger Birnbaum stepped down Wednesday as co-chairman and co-CEO of Metro-Goldwyn-Mayer to become an exclusive producer at the studio.
Boral CEO steps down, shares slip Updated: 17:06, Tuesday May 22, 2012 Shares in building products maker Boral are down after chief executive Mark Selway stood down after apparently losing the board's support.