Oprah Winfrey takes her final bow after 25 years as chat show queen

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Oprah Winfrey takes her final bow after 25 years as chat show queen

Four former presidents have sat on Oprah's sofa over the course of her chat show – but in May 2011, she presented a landmark interview with sitting leader Barack and his wife Michelle Obama.

It was the couple's first appearance together on the show since 2006, and helped Oprah mark the end of her 25-year reign