CHICAGO — After sharing the cover of her magazine with her slimmer self a couple of months back, Oprah Winfrey is for the first time sharing it with somebody else: first lady Michelle Obama.

Winfrey showed off the cover of the April issue during "The Oprah Winfrey Show" broadcast yesterday. The media mogul had gone solo on the "O" magazine cover for nine years.

In the issue that will hit newsstands March 17, Winfrey interviews the first lady about topics ranging from her decorating philosophy to how she hopes she can help other women.

RIHANNA WOULD TESTIFY AS WITNESS

LOS ANGELES — Rihanna's attorney says the singer would testify against Chris Brown if called as a witness in her boyfriend's assault case.

Donald Etra, who is representing the 21-year-old Barbados native, said yesterday that Rihanna would be required by law to testify if prosecutors subpoena her.

Etra appeared in court Thursday when Brown made his first appearance on charges of assaulting and making criminal threats to his superstar girlfriend. Brown's arraignment was postponed until April 6.

Etra said Rihanna did not want a "no contact" order issued against Brown, but that she will report any violations of an order prohibiting the 19-year-old singer from threatening, harassing or harming his girlfriend. A court order grants her the authority to record any violations of the order.

Brown was arrested Feb. 8 stemming from an altercation that police say he had with Rihanna in a car in an upscale Los Angeles neighborhood.

UNIVERSAL WINS EMINEM SUIT

LOS ANGELES — Rapper Eminem's former production company, F.B.T. Productions LLC, yesterday lost its lawsuit against Universal Music Group that sought to claim a greater share of the revenue from digital downloads of the artist's works between 2003 and 2008.

F.B.T.'s lawyer, Richard Busch, said a federal jury voted unanimously in favor of the defendants, which included Dr. Dre's record label, Aftermath Records, and its distributor, UMG's Interscope Records. Universal is a unit of France's Vivendi SA.

F.B.T. sought to have digital sales by such services as Apple Inc.'s iTunes music store be treated under a master recording licensing deal between Universal and Apple, in which case F.B.T. would be entitled to its share of a 50-50 split with Universal. Part of that 50 percent would have been split with Eminem.

Instead, the record label had paid F.B.T. and Eminem a total of 12 percent of the sales, the rate agreed upon for sales of physical albums.

BEATLES VIDEO GAME OUT IN SEPT.

The creators of Rock Band have chosen Sept. 9 — or 09/09/09 — as the North American release date for "The Beatles: Rock Band," the first edition of the video game to be engineered around the music of a single act.

It is being described as an "experiential progression through and celebration of the music and artistry of the Beatles," rather than simply a regular edition of Rock Band using the Fab Four's music. It will be released in configurations for Sony PlayStation 3, Microsoft Xbox 360 and Nintendo Wii units.

Part of the experience will come from game controllers that copy instruments played by the group. The complete package will carry a list price of $250.