For over two decades, Oprah Winfrey hosted The Oprah Winfrey Show, thus becoming one of the richest and most powerful personalities on television and in the media in general. Watched by millions of viewers for each episode, the show itself represents a stepping stone in television history – but that chapter will close in September 2011, when the next season comes to an end, as the Los Angeles Times reports.

Oprah is expected to make the announcement on the upcoming episode of the show. The reason for ending the hugely popular syndicated show seems to be that Oprah has serious plans of starting her own network, which will carry another, similar talk show, reports say. The star herself has kept very quiet about her plans for the future and was not immediately available for comment at the time of writing.

“Although she has kept mum about her plans, Winfrey, 55, is expected to furnish a new show to OWN: the Oprah Winfrey Network, the long-delayed cable outlet she is starting in partnership with Discovery Communications. The network is scheduled to roll out in 2011 in about 75 million US homes. The media personality and mogul – whose show has served as the main pedestal from which she has engaged newsmakers high and low, transformed obscure products and personalities into runaway successes, and preached a gospel of self-empowerment to her devoted, largely female audience – is betting that, in a world of ever-fragmenting audiences, the future lies with creating her own branded network,” the aforementioned publication writes.

While Oprah herself is not available for comment, Tim Bennett, president of Harpo Inc., Winfrey’s Chicago-based production company, has sent out an e-mail to all partners announcing the upcoming departure. Somehow, said notification leaked to the media and is now being used as concrete confirmation that, indeed, come September 2011, when the upcoming season of The Oprah Show ends, an era will also come to an end.

“The sun will set on the Oprah show as its 25th season draws to a close on September 9, 2011. We welcome you to share this news this evening with your colleagues and viewers. As we all know, Oprah’s personal comments about this on tomorrow’s live show will mark an historic television moment that we will all be talking about for years to come. We want to thank you for the partnership and friendship we have shared over the years. Your invaluable support has helped us to create the phenomenon of the Oprah Show that we’ve all been so proud to be a part of for the last 24 years. My staff and I will be calling all of you directly tonight and tomorrow. We look forward to speaking with you,” Bennett writes in said letter.