Disney has launched a line of Hannah Montana-inspired merchandise—140 items, including clothes, watches, bedding, luggage, shoes, makeup, spa kits, and toys. These products sell in mass-market retailers like Macy’s, Kmart, and Target, and on January 29 Wal-Mart announced that it would be creating specialized Hannah Montana boutiques within many of its 750 U.S. stores, insuring that the global retail powerhouse would become Hannah Montana central.

Even in the annals of Disney’s vaunted history of childhood icons, there’s never been anyone quite like Hannah Montana. “Miley is the first star to have multiple deals across several aspects of the company, including TV, film, music, and consumer products,” said Patti McTeague, a spokesperson for the Disney Channel. While she notes that the company has had recent success with tween stars like Hilary Duff and Raven Simone, both of whom continue to be revenue-generating celebrities for the company, “as a franchise, it’s a unique association we have with Miley.”

Disney praised the Hannah Montana properties in its upbeat first-quarter earnings report for fiscal 2008, which found revenues for the company rising by 9 percent compared with the previous year. The concert tour, merchandise, and video games all got positive mentions in Disney’s earnings statement.

Unlike stars who had a hard time translating teen fame into adult stardom, Cyrus (who turns 18 in 2010) is already laying the foundation for the future. On her TV show, she plays Miley Stewart, a teenager with a secret identity: international pop star Hannah Montana. Only her family—and viewers—are in on the secret. On her sold-out tour, she sings the first half of each concert “in character” as Hannah Montana, then the second segment as herself, Miley Ray Cyrus, teenage singer-songwriter. Besides being a neat marketing trick worthy of a metafiction book, Cyrus is making sure she’s not limited to the tween persona that she will, inevitably, outgrow.

It’s a deft move on her—or her management team’s—part, says Wood. “Her audience loves Miley and they love her character Hannah,” he says. “It gives her a lot more options in terms of how she can develop her character and herself. It’s the best of both worlds.”

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