Does it seem, sometimes, that it’s Oprah’s World and we’re just living in it?

There she is on TV everyday — not only on The Oprah Winfrey Show but also a virtual presence, at least, on Dr. Phil, Dr. Oz, and other shows that she and her company, Harpo, have created.

She’s on every cover of her magazine, O, telling us what to eat, what to buy, and how to live.

For me this past week? Well, I really have been living in Oprah’s world.

“Oprah’s Next Act,” my cover story in the new issue of Fortune, hit the web and will be on newsstands Monday.

And last night: “Hi, it’s Ms. Next Act,” a voice intoned when I answered my cell phone at 7 o’clock.

“Who?” I replied. “Ms. Next Act!”

Yes, it was Oprah calling about the story about her. I had to thank her for being so forthcoming when I interviewed her two weeks ago, in her Chicago office, about OWN: The Oprah Winfrey Network.

The cable network is due to  launch 1/1/11, though, as I describe in the Fortune piece, Oprah so feared this “next act” of her career that her 50-50 deal with Discovery Communications almost collapsed.

Why the remarkable candor? Oprah said last night that she can’t stand it when guests on her show don’t tell all — or even worse, deliver b.s.

“You’re too smart for that,” she said, “and I’m too smart for that too.”

It’s nice when a mogul tells it like it is, even though she doesn’t have to.

Speaking of TV, I’ve been on the circuit — CNBC’s Squawk Box, MSNBC’s Andrea Mitchell Reports, CNN’s American Morning, NBC’s Today — talking about the Oprah story and the 2010 Most Powerful Women list, which appears in the same issue of Fortune.

On Today this morning, I talked about No. 1, PepsiCo CEO Indra Nooyi, and No. 2, Kraft Foods CEO Irene Rosenfeld, as well as No. 6, Oprah.

These TV gigs are interesting to do, mainly because you never know who you’ll meet at the studio. This morning at Today, I shared the makeup room with the irrepressible Tony Bennett. He looks darn great at age 84.

And today at CNN’s American Morning, I shared the green room with Cameron and Tyler Winklevoss, the former Harvard classmates of Facebook founder/CEO Mark Zuckerberg who claim he stole their idea. The strapping identical twins (who reportedly received $65 million in a settlement of their lawsuit) are making the TV rounds, talking up The Social Network, the just-released movie about Facebook’s founding.

They told me they liked the film — though they said they’re itching to get to London to do what they love most: rowing. After coming in sixth at the Beijing Olympics two years ago, they’re training for the 2012 London Games.