The call from the White House came in at 9:43 p.m. He was given the news in strict confidence and began racing to the New York office, switching back and forth on his satellite radio between CNN and MSNBC and listening to reporters dancing around news that they knew but couldn't report yet.
That led to a spate of stories about TV networks looking slow in comparison to social networks Twitter and Facebook, where rumors about bin Laden swirled.
"You could learn about this story on social media Sunday night, but you couldn't learn what we told you about it," Williams said. "The tonnage, the raw material came from journalists, and it came in parcels larger than 140 characters."
He spoke last week in a conference room off the studio where Rose tapes his PBS show, a few days after his Letterman appearance. Sometimes it seems Williams is on other programs as much as his own. But as long as they don't interfere with his NBC work, he feels the guest shots benefit all concerned.
He's all business in a discussion with historian Doris Kearns Goodwin and two journalists, an interview with NBC's Richard Engel, and retaping introductions because of faulty scripts. It's only when the studio backdrop flashes, "Happy birthday, Brian" (he's 52), that he swiftly switches modes. He pretends to be a PBS fundraiser seeking pledges by airing doo-wop specials.
Only a few years ago NBC executives privately wondered how to make viewers aware that the formal, sometimes stiff guy they saw onscreen was the amusing man they knew.
How far gone are those days? New York magazine just ran a piece on Williams' comic stylings on such shows as "Saturday Night Live" and "The Daily Show."
Still riding high in the ratings, an achievement considering the collapse of NBC entertainment around him, and now the dean of network evening news anchors, there's a good chance Williams has his job for as long as he wants it.
"I'll never walk away because of complaints about the job," he said. "My wife is under orders to know when it's time and to yank me firmly from the stage. She will know."
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