*Thousands of Oprah Winfrey fans are expected to pack Chicago’s United Center today for a star-studded double-taping of her talk show as it inches toward its finale.

The guest lineup for “Surprise Oprah! A Farewell Spectacular” is a secret, but Winfrey’s producers have promised the biggest names in Hollywood.

The celebrity response “has been a resounding `yes,'” executive producer Sheri Salata told the AP. “Celebrities from film, television and music feel a deep appreciation for the support they have received from Oprah and the show over the years. Oprah will be very touched by that gratitude.”

Tuesday’s taping will air May 23 and 24, before Winfrey’s final show on May 25.

“Oprah is in great spirits, energized and taking in every last bit of these final days,” said Salata, who figures prominently on “Season 25: Oprah Behind the Scenes.” The show follows the final season Winfrey’s talk show and airs on her new cable network.

“The producers are a little teary-eyed — it’s hard to say goodbye,” Salata said.

Harpo Productions received more than 154,000 ticket requests for seats to Tuesday’s event. Tickets were free and distributed to fans through a lottery.

The United Center is home to the Chicago Bulls and Chicago Blackhawks with a seating capacity of more than 20,000. It is just blocks from Winfrey’s long-time studios.

Meanwhile, as Winfrey begins to focus 100 percent of her attention on her cable channel OWN, Radar Online is reporting that the talk show host is attempting to woo her good friend Maria Shriver to host her own show.

“Oprah approached Maria several months ago about getting involved at OWN,” a source close to Shriver tells Radar Online. “A talk show featuring Maria as the sole host was discussed. But now that Maria has formally separated from Arnold, Oprah is on a full court press to lock Maria up.”

The news comes a day before Schwarzenegger disclosed he had fathered a child with one of his staffers.

Shriver and Oprah met years ago and formed a tight bond when both began pursuing careers in journalism. Shriver, an Emmy award winner, was a correspondent for “Dateline NBC” up until 2003 when her husband’s run for governor presented a possible conflict of interest. She went on leave and later quit after Schwarzenegger won.

“To this day, she’s still angry she had to leave,” the source says. “She always felt Arnold never sacrificed anything for her while she sacrificed for him. She never had to work but she loved being a journalist.”

But Winfrey has some competition as other networks have also reached out to Shriver in the hopes of scooping her up. “Maria is looking at make a comeback and she is getting tons of offers from the major networks,” the source added. “Maria’s children are almost all grown up, her youngest son is 15. It’s not a matter of if Maria will return to television, but when.”