Oprah Winfrey has decided to end her talk show, The Oprah Winfrey Show, at the end of her 25th season on Sept. 9, 2011. The news, following months of speculation, was first reported by Chicago’s ABC affiliate. A spokeswoman from Harpo Studios confirmed to EW that the Queen of Daytime told her staff today and will explain the reasons behind her decision during the talk show Friday. It’s been speculated that Winfrey could make such a move in order to focus her attention on the planned Oprah Winfrey Network, her joint venture with Discovery Communications that has yet to announce a concrete launch date.

Winfrey’s talk show contract with distributor CBS Television isn’t set to expire until 2011, but her spokesperson had indicated that she would announce her decision before year’s end. Published reports have suggested that Winfrey would want to move her talk show to OWN in an effort to boost its viability but an insider tells that Winfrey will not move it but will rather appear prominently on the fledgling network. The date of OWN’s actual launch date remains elusive; though the network has long indicated that it would premiere in 2010, rumors persist that it will be delayed another year to give Winfrey more time to build the chick-friendly lineup (so far, OWN has only announced a handful of shows in development including Lisa Ling Investigates and a sex-therapy series from Sirius XM host Dr. Laura Berman).

Speculation that Winfrey would move her talk show to OWN hit a fever pitch earlier this month when Lisa Erspamer, the former co-exec producer of The Oprah Winfrey Show, jumped ship to help develop new programming for the Los Angeles-based OWN. In the meantime, CBS TV had held out hope that it would remain in business with Winfrey – until now. “We have the greatest respect for Oprah and wish her nothing but the best in her future endeavors,” said a company spokesman. “We know that anything she turns her hand to will be a great success. We look forward to working with her for the next several years, and hopefully afterwards as well.”