FACTBOX: Oprah Winfrey says will end talk show in 2011

(Reuters) - Oprah Winfrey has long been considered among the most influential television talk show hosts in the United States for her in-depth interviews of politicians, celebrities and newsmakers of the day.

She will end her current program, "The Oprah Winfrey Show," in September 2011 and industry watchers expect her to move to the new cable TV network OWN, which she is forming in a joint venture with Discovery Communications Inc. Following are some facts about Winfrey and her program.

* Winfrey, 55, was born on January 28, 1954 to a single mother in rural Kosciusko, Mississippi, and at age 19 became the youngest person and first African American woman to anchor the news at Nashville's WTVF-TV.

* In 1984, she moved to Chicago to host WLS-TV's morning talk show, "AM Chicago," and in less than a year, it was renamed "The Oprah Winfrey Show." She eventually came to own the program through her company Harpo Inc, and it became nationally syndicated in 1986.

* In 1985, she starred in director Steven Spielberg's film "The Color Purple," earning an Oscar nomination for best supporting actress. Winfrey has produced other movies including 1998's "Beloved" and the currently playing "Precious: Based on the Novel 'Push' by Sapphire".

* Her book club has championed numerous authors, and her O, the Oprah Magazine, is a widely read style guide.

* On her show, she gave Barack Obama national exposure that helped him launch his presidential campaign; and an appearance by Tom Cruise damaged his career when he jumped on her couch to proclaim his love for actress Katie Holmes.

* "The Oprah Winfrey Show" is currently the top-rated U.S. daytime talk show, averaging 7.1 million viewers this year.

* Winfrey was recently ranked No. 141 on Forbes' magazine's list of 400 richest Americans of 2009 with a net worth of $2.3 billion.

(Reporting by Bob Tourtellotte; editing by Jill Serjeant and Todd Eastham)