When Katie Couric greeted Beyonce Knowles with a hug before their "20/20" interview, she couldn't resist giving the world's most famous, fabulous and fierce baby belly a little rub. "I bet your mom does it all the time, and your sister," Couric said. "Oh yeah. I mean, I can't walk. I have somebody holding me and hugging, and there's going to be so much love around the baby," Knowles said, laughing. Last summer, while Knowles performed four nights of sold-out shows at New York City's Roseland Ballroom, a sequinned mini-dress was strategically draped over her growing belly. The concerts have been captured on a DVD, "Live at Roseland: Elements of 4," which was released this week. Knowles, 30, already has the resume of a legend: singer, songwriter, actor, fashion designer and model. So it's no surprise that for the concert film she was performer, director, choreographer and producer -- all in one. Beyonce's co-parent and husband is, of course, hip-hop star/mogul Jay-Z. In August, Jay was among the thrilled onlookers when Knowles "announced" her pregnancy at the MTV Video Music Awards. Knowles sang her hit "Love On Top" -- while hiding her secret under her top. After the song, she opened her jacket and rubbed her belly, smiling. The audience roared, and the instant buzz made Twitter history: By 10:35 p.m. people were posting a record 8,868 tweets per second, the company said. When Couric asked how she decided on the gesture, Knowles said: "Physically I was starting to show, so it was only a matter of days before someone zoomed in. So I just wanted it to be from me, and I wanted it to be something that was a celebration of something so beautiful. And I didn't want to release a picture or a statement. I figured the biggest statement was to -- just be." Was she surprised by the reaction?