Pew Internet have updated their data that shows who is using Twitter and other social media sites. As we noted yesterday, 18 percent of online U.S. adults are now active on Twitter, up a full two percentage points from February of this year, and more than double Twitter’s total user base in November 2010.

But who are these people? According to Pew’s findings, the typical Twitter user is an 18-29 year-old educated minority with a well-paying job, and slightly more likely to be male than female.

Pew surved 1,895 adult internet users in the United States and found that 18 percent of men and 17 percent of women use Twitter. Hispanic (28 percent) and black (27 percent) users are far more likely to use the service than whites (14 percent), and 18-29 year-olds (30 percent) make up to close to one-third of all users.

Additionally, Twitter users are typically educated (39 percent have at least some college experience) and hold a pretty decent job (42 percent earn $50,000 per annum or more).

The survey also revealed that use of Twitter across all age demographics is on the rise, although the 18-29 subset is down marginally since its peak at the tail-end of last year.

(Source: Pew Internet.)