Pew have updated their annual look at who is using Twitter – you may recall that in their 2011 report it was revealed that some 13 percent of online adults were using the micro-blogging platform (up from 8 percent in 2010), and that the typical user skewed towards an 18-29 year-old non-white male.

Fast-forward another year, and what has changed?

Not much, to be honest. While Pew’s latest findings reveal that overall Twitter usage is up a couple of percentage points to 15 percent of online adults, the service still performs strongly with minorities, with more than one quarter of black internet users (28 percent) and 14 percent of Hispanic users active on the platform. Conversely, just 12 percent of whites use Twitter.

The 18-29 demographic continues to be the most highly represented at 29 percent, ahead of those aged 30-49 (14 percent) and 50-64 (9 percent).

The only notable difference: women (15 percent) have taken the lead from men (14 percent), albeit marginally.

While 15 percent is still a fairly small number and a long way off from Facebook’s levels, Pew observed that Twitter usage has risen steadily since November 2010, excluding a slight dip in August of last year.

Where Twitter has gained significant ground (which has likely bled across to overall use) is in mobile – one in five (20 percent) of smartphone owners are Twitter users, and 9 percent of all internet users have accessed Twitter via their phone. Otherwise, mobile data for Twitter correlates accordingly with the age and ethnicity representation above.

For more detail on the 2012 report, please visit the Pew Internet website.