Oprah Winfrey's six-month-old network OWN was down 24 percent in adult viewership in May, compared to the May 2010 ratings of Discovery Health, which OWN replaced, according to TVbytheNumbers. Its numbers were down in demographics versus Discovery Health's May '10 ratings across the board. In women 18-34, the drop was 24 percent. For women 18-49, it was 19 percent. In women 24-54, likely its target demo, it was down 17 percent. And in adults 18-49, it was down a whopping 30 percent. Oprah replaces OWN CEOAlmost from the time of its January 1 debut, OWN has struggled to even match...