Teens tout the ease of use and the ability to send the equivalent of a text message to a circle of friends, often a smaller one than they have on crowded Facebook accounts. They can have multiple accounts and don't have to use their real names. They also can follow their favorite celebrities and, for those interested in doing so, use Twitter as a soapbox.

The growing popularity teens report fits with findings from the Pew Internet & American Life Project, a nonprofit organization that monitors people's tech-based habits. The migration has been slow, but steady. A Pew survey last July found that 16 percent of young people, ages 12 to 17, said they used Twitter. Two years earlier, that percentage was just 8 percent.

"That doubling is definitely a significant increase," says Mary Madden, a senior research specialist at Pew. And she suspects it's even higher now.

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