Winfrey's daytime show wasn't all about interviews, of course. But in her last few seasons, she sat down for conversations with the likes of Tina Fey, Elizabeth Edwards, Michelle Obama, Madonna, Denzel Washington, Jerry Seinfeld, Richard Branson and Beyonce.
The audience was primarily women but, as Cruise proved with his eager declarations of love for Katie Holmes in 2005, the cultural impact could spread beyond the afternoon.
"Doing an interview on one of those shows was like Johnny Carson asking you to come sit with him after you've done your stand-up," said Robert Thompson, director of the Bleier Center for Television and Popular Culture at Syracuse University. "If there was any equivalent to playing the Palace at the end of the 20th and beginning of the 21st centuries, being on 'Oprah' might have been it."
While Thompson said that "half the people can't find OWN on their cable television," that may underestimate Winfrey. The "Oprah's Next Chapter" episode with Houston's family in March premiered to 3.5 million people, Nielsen said. Many others heard about it or saw clips.