It looks like Oprah Winfrey is calling it quits — in 2006.

The omnipresent talk-show queen, who is one of the wealthiest women in the United States and among the most powerful media executives in the world, says she's retiring from her popular Oprah Winfrey Show four years from now. 

Winfrey, whose syndicated daily program is the highest-rated daytime talk show on TV, has signed on to host the show for another two seasons beyond her current contract, which was set to expire in 2004. 

Winfrey was not available for comment. 

Yesterday, industry observers were not completely convinced it's all over for Oprah, even in 2006. 

"She's said this before  that she'd done what she set out to do and it was time to for her to move on," Mediaweek's TV industry analyst, Marc Berman, said. 

About five years ago Winfrey suggested that she was planning to retire from daytime TV. 

But she had a change of heart and renewed her contract through 2000. Since then she's signed extensions that keep her with the show through 2004 — and now she's added another two years to the deal. 

"Oprah is a businesswoman. If her ratings hold up during the 2005-06 season, she may decide to change her mind," Berman said. 

Winfrey's talk show is watched by an estimated 7.1 million people every day. Her magazine O is of the most successful new titles in the publishing industry. Last year Forbes magazine estimated Winfrey was worth in excess of $900 million.

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