MySpace Music is adding audience at a great pace, according to Nielsen Online’s June Data.  Since the site’s launch in September 2008, unique visitors to the music.myspace.com subdomain have increased 190 percent — growing from 4.2 million unique visitors to 12.1 million in June 2009.

Year-over-year traffic to the URL has increased 1,017 percent. In June, unique visitor traffic ranked third in the music category, behind category leaders AOL Music and Yahoo! Music – and ahead of other category leaders such as MTV Networks and Pandora.

People between the ages of 12 and 17 were 2.4 time more likely than the average active Internet user to visit music.myspace.com. Visitors between 18 and 24 were 2.2 more likely than the average Internet user to visit the site in June.

MySpace Music launched last September as a joint venture with the major record labels. Recently, there were reports that the labels were disappointed with lackluster returns in terms of actual sales. However, new surveys such as this one indicate that MySpace Music may well be heading in the right direction by combining the social networking features of the main portal with on-demand music options.