Denise Petski, Ted Johnson ABC News’ World News Tonight with David Muir topped its broadcast rivals in the first week of the new season.The newscast drew 8.50 million viewers, compared to 7.33 million for NBC Nightly News with Lester Holt and 5.15 million for CBS Evening News with Norah O’Donnell.In the 25-54 demo, World News Tonight had 1.67 million, to 1.48 million for NBC Nightly News and 930,000 for CBS Evening News.