Not so fast.
NBC's Brian Williams actually still is the evening news champion.
With egg on its face, Nielsen on Tuesday released adjusted audience totals after correcting a software glitch that mysteriously added viewers to ABC's totals -- while robbing the other networks of some of their hard-fought viewers.
It turns out that Muir wasn't the leader after all. NBC's stalwart "Nightly News with Brian Williams" maintained its win streak that has been in place for 265 consecutive weeks, or more than five years.
Nielsen last week reported that ABC's “World News Tonight” had averaged 8.42 million viewers during the week of Sept. 29 and that NBC's "Nightly News" had garnered 8.25 million viewers.
In fact, NBC attracted 170,000 more viewers than "World News Tonight" during that week.
“We are pleased that the corrected numbers confirm that 'NBC Nightly News' is the No. 1 news broadcast in America, and has been for the last 265 weeks," NBC News said in a statement.
The revised Nielsen numbers showed that NBC's newscast with Williams attracted 8.3 million viewers while ABC's program drew 8.1 million viewers.
Nonetheless, the evening news has become a horse race with ABC's Muir notching gains during his one month as anchor, particularly in the 25-to-54 demographic.
The ABC program's audience in that demographic has increased 8% compared with the same week last year when Diane Sawyer anchored the broadcast. ABC has edged past NBC in that category.
Muir took over for Sawyer on Sept. 1.
"'World News Tonight' is in the tightest evening news race in several years and we're honored the viewers are responding," an ABC News representative said in a statement.
Nielsen's software glitch had been crediting ABC with other networks' viewers when the audiences totals were resifted to include viewers in the western half of the United States.
Networks noticed the problem last month as the new prime-time season kicked off and ABC's numbers perked up when time zone adjustments were made.
The software problem stretched back to March, Nielsen acknowledged last week, raising questions about the accuracy of ratings released during the spring and summer.
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