According to the Pew Internet & American Life Project, 19 percent of Internet users now say they use Twitter or another service to share updates about themselves, or to see updates about others. This represents a significant increase over previous surveys conducted in December 2008 and April 2009, when 11 percent of internet users said they used Twitter or another micro-blogging service.
Three groups of Internet users are responsible for driving the growth of this activity: social networking site users, mobile Internet users, and adults under age 44.
In addition, the more devices someone owns, the more likely they are to use Twitter or another service to update their status. Fully 39 percent of Internet users with four or more internet-connected devices (such as a laptop, cell phone, game console, or Kindle) use Twitter, compared to 28 percent of Internet users with three devices, 19 percent of Internet users with two devices, and 10 percent of Internet users with one device.
The median age of a Twitter user is 31, which has remained stable over the past year. By comparison, the median age for a LinkedIn user is now 39, down from 40, while the median age for a Facebook user is now 33, up from 26 in May 2008.
According to Pew, it will become more difficult to track status updating as an independent activity as social network updates feed into Twitter and vice versa. For now, it is clear that a "social segment" of internet users is flocking to both social network sites and status update services. This segment is likely to grow as ever more internet users adopt mobile devices as a primary means of going online.
At SES Chicago 2009, Jackson will be speaking at the "SEO Through Blogs & Feeds" session, and Krum will be speaking at the "Cool Mobile Apps, Augmented Reality - It's a Brave New World!" session.