Twitter Tweeters Comprise One-Fifth Of Internet Users

The Pew study found that almost one-fifth, or 19 percent, of Internet users now Tweet to share personal and business information about themselves, representing an 8 percent increase from a survey conducted in April 2009.

Altogether, the study found that Twitter's recent growth is driven largely by three types of users: those who regularly post content on social networking services like MySpace and Facebook; smartphone and mobile device users; and young Web surfers.

And Twitter is growing by leaps and bounds in just about all demographics. Twitter has experienced the most growth with younger users. Pew researchers found that the number of people aged 18 to 24 using some type of status update service has doubled from last year, attributable in large part to Twitter's rapid success.

However, unlike its counterparts, the average age of Twitter users has remained relatively static, with a median user age of 31. Other social networking sites are still finding their core demographic. MySpace has grown younger, with a median age of 26, down from 27 in May 2008. LinkedIn also fell to 39 from 40. Meanwhile, Facebook has aged a bit, up to 33 from 26 more than a year ago.

The Twitter fad hasn't immediately been embraced by all. Popularity for the micro-blogging site has lagged with users aged 45 to 54 and 55 to 64, each of which comprised a respective 10 percent of the site's users. Those over 65 only represented 4 percent of Twitter users. Some initially were put off by the micro-blogging site, which limits posts to 140 characters, before adopting Twitter as a social networking tool.

In addition, the study found that the more gadgets a person owns, the more likely he or she is to use Twitter to post status updates. Almost 40 percent of users with four or more Internet-connected devices use Twitter, compared to only 28 percent of users who own a mere three Internet-connected devices, 19 percent of users with two devices and 10 percent of Internet users with one device.

And of the 54 percent of users with wireless connection via laptop or mobile phone, almost a quarter said they regularly post updates on Twitter.

Regular social networking junkies were also more likely to Tweet (35 percent) compared to 6 percent of their non-social-networking peers who use the micro-blogging site. The Pew study also suggested that a "social segment" of users -- those who regularly post on social networking sites and status update services such as Twitter -- will likely grow as more users rely on mobile devices for connection to the Internet.