Oprah Winfrey, shown Nov. 1, announced Friday that her day-time talk show will end in 2011. (Chris Pizzello/Associated Press)An emotional Oprah Winfrey pledged to fans that she would "knock your socks off" with the 25th and final season of her eponymous talk show, set to end in 2011.

The chat show diva and media mogul's Harpo Productions confirmed on Thursday evening that she would indeed end in her influential program after a quarter-century.

Winfrey addressed the issue herself in Chicago on Friday morning, at the close of a live taping of her hour-long show.

"This show has been my life and I love it enough to know when it's time to say goodbye. Twenty-five years feels right in my bones, and it feels right in my spirit. It's the perfect number, the exact right time," Winfrey, who at one point wiped away tears, told her studio audience.

The show is slated to end on Sept. 9, 2011, chosen because it will mark 25 years to the day that Winfrey began her program.

In the meantime, she said she hoped viewers would continue with her for the next 18 months and that she would work with her staff to present a blockbuster final season.

"We are going to knock your socks off," she said. "The countdown to the end of The Oprah Winfrey Show starts now."

The 55-year-old Winfrey did not share her future plans, but noted that "over the next couple of days, you may hear a lot of speculation in the press about why I am making this decision now, and that will mostly be conjecture."

'This show has been my life and I love it enough to know when it's time to say goodbye.'—Oprah Winfrey

In a statement, Harpo Inc. said that once show ends production in 2011, Winfrey "plans to appear and participate in new programming" for the Los Angeles-based Oprah Winfrey Network, a much-delayed cable TV venture with Discovery Communications Inc. The network will replace the Discovery Health Channel and will debut in some 74 million homes when it launches in January 2011.

Stratospheric rise

Born to a single mother in rural Mississippi, Winfrey rose to become a respected broadcast journalist in Nashville and Baltimore, before moving to Chicago in 1984 to host a morning talk show that was renamed The Oprah Winfrey Show a year later.

In 1986, after establishing her own company to produce the show, Winfrey's program went into syndication and began its rise as an American pop culture powerhouse.

She is an Oscar nominee for her supporting role in the 1985 film adaptation of The Color Purple and, over the years, Winfrey has expanded into a variety of other media, including magazine publishing and satellite radio broadcasting.

She has also wielded considerable influence in publicizing the people, places and things she supports, from her politics (as a vocal supporter of U.S. President Barack Obama during his election campaign) to cultural creations (as executive producer of the musical The Color Purple and the new film Precious: Based on the Novel Push by Sapphire) to her favourite charities (including opening a namesake all-girls school in South Africa).

The term "the Oprah effect" was also coined to describe the skyrocketing interest in, sales of and publicity for any product Winfrey features on her show — from an author's new book, to a singer's new album, to a favourite baked good or household gadget.

Distributed by CBS Television from Chicago and seen in more than 140 countries around the globe, The Oprah Winfrey Show is the top-rated U.S. daytime talk program, viewed by an estimated 42 million per week in the U.S. alone.

Though in the last year her ratings have slipped by seven per cent, her powerful multimedia empire still makes her net worth $2.7 billion US, Forbes magazine said earlier this year.

With files from The Associated Press