Source: Bill Zwecker / Chicago Sun-Times Motion Picture Academy sources say Oprah Winfrey is topping the list of candidates to host the 84th Oscars next February. If the widely seen gig is accompanied by a behind-the-scenes special and a post-Oscars show airing only on the Oprah Winfrey Network, it would give the struggling cable channel some added exposure. But I'm hearing that is a very separate potential deal. After all, ABC continues to have exclusive rights to Oscar broadcasts — [...]