(Cover) - EN Showbiz - Madonna and Simon Cowell were among the stars to attend an after-party celebrating Oprah Winfrey's final shows.

The talk show mogul has taped the final episodes of The Opray Winfrey Show, which is wrapping up after 25 years. A host of celebrities appear in the last programmes and just as many turned out to show their support at the United Center in Chicago, where a party was held to celebrate Oprah's career.

Pop star Madonna was keen to shower the talk show host with praise. "I like her because she's smart, she's really smart. I like anyone who encourages people to read. She's very dignified and she just keeps going," she told Extra.

Music supremo Simon was just as glowing about Oprah. He finds it hard to believe she has managed to stay relevant for so long, especially at a time when she has so many rivals vying for her crown.

"To make it for two-and-a-half years is a miracle, 25 years still at the top, all these big stars come out, no egos, all for her... it's a special night," he said.

"She reinvented this genre of TV, most importantly, what we all learned is without your audience you have no show. You have to respect your audience, and she respects them."

Usher, Jamie Foxx and Rosie O'Donnell were also in attendance.

The final episode of The Oprah Winfrey Show will air on May 25. (C) Cover Media