Oprah Winfrey's OWN Cast of Characters: Rosie O'Donnell, Gayle King, Julia Roberts and More

Aug. 9, 2010 — -- With a name like Oprah's, it has to be big.

OWN: The Oprah Winfrey Network is slowly but surely building up to be a broadcast behemoth. Besides the media mogul herself, a slew of celebrities and talk show staples have agreed to appear on the channel, from the A-list actress with a megawat smile (Julia Roberts) to the controversial comedian who can't be kept off the air (Rosie O'Donnell).

Below, a look at the cast of characters Winfrey's assembled to front her cable television network, slated to debut in at least 80 million homes come January:

Rosie O'Donnell's past talk-show troubles haven't soured her from the circuit. The former moderator of "The View" announced last week that she'll return to daytime TV with a show on OWN. "It's an honor and a privilege to work with Oprah Winfrey on her network," O'Donnell said in a joint statement with Winfrey. "I'm excited to be back on daytime television."

TV is familiar turf for the comedian: her last solo talk show, "The Rosie O'Donnell Show," ran from 1996 to 2002 and won a slew of daytime Emmys. But her more recent stint on daytime television was marked by squabbles, not statues. Chairing the coffee table of "The View" from 2005 to 2007, O'Donnell sparked memorable on-air spats with Donald Trump and fellow "View" host Elisabeth Hasselbeck.

But it sounds like O'Donnell's new venture will be sunnier: the statement she released with Winfrey promises a "fun, uplifting show with Ms. O'Donnell's playful and energetic style."

Catching Julia Roberts in action normally involves $7.50 and a bucket of popcorn. But Winfrey convinced the "Eat, Pray, Love" star to take her act to the small screen. Roberts will host and be executive producer of "Extraordinary Moms," a documentary film dedicated to mothers struggling to better their families, for OWN.

It's part of OWN's monthly "Documentary Film Club" which features a host of celebrity-produced projects. Mariel Hemingway looks at the legacy of suicide in her own family in "Seven Suicides," Gabriel Byrne explores homelessness in Nashville with "Tent City," Goldie Hawn investigates positive psychology in "Searching for Happiness," and Forest Whitaker goes inside a Lousiana prison's hospice wing in "One Last Shot."

Oprah Winfrey's OWN A-List Hosts

While OWN offers a platform for anything-but-ubiquitious documentaries, it also dabbles in a cable TV staple: reality TV. Country crooner Shania Twain stars in "Why Not? With Shania Twain," which will follows her trying to revive her personal and professional life after splitting from her husband, music producer Robert John "Mutt" Lange.

Winfrey's BFF, Gayle King, will get top billing on OWN. She'll host "Gayle King Live!," a TV version of her XM Satellite Radio show.

Famed reality TV producer Mark Burnett's OWN show stirred scandal months before hitting screens. "Your Own Show: Oprah's Search for the Next TV Star" came under fire after allegations that Winfrey had rigged voting for the "American Idol"-style search for budding hosts. It turned out spam blogs were to blame for skewed votes in the competition between disabled contestant Zach Anner and schoolteacher Phyllis Tucker-Wicks.

Two OWN shows offer a smorgasbord of stars: "Oprah Presents: Master Class" and "Visionaries: Inside the Creative Mind." The first features celebrities dispensing life lessons. Jay-Z, Bono, Toni Morrison, Simon Cowell, Lorne Michaels and Condoleezza Rice are rumored to have signed on. "Visionaries" looks at the minds of modern day artists, including James Cameron, Lady Gaga, and Annie Leibovitz.

Of course, the channel couldn't be complete if Winfrey herself weren't on screen. "Behind the Scenes: The Oprah Show Final Season," is set to begin in January, as the network launches. She'll also host the aptly titled "Oprah's Next Chapter," a one-hour series in which she'll do on-location interviews. New channel, new format, same Oprah.