The uptake of social network sites (SNSs) has been highly trend-driven, with Friendster, MySpace, and Facebook being successively the most popular. Given that teens are often early adopters of communication technologies, it seems reasonable to assume that the typical user of any particular SNS would change over time, probably becoming older and covering different segments of the population. This article analyzes changes in MySpace self-reported member demographics and behavior from 2007 to 2010 using four large samples of members and focusing on the United States. The results indicate that despite its take-up rate declining, with only about 1 in 10 members being active a year after joining, the dominant (modal) age for active U.S. members remains midadolescence, but has shifted by about 2 years from 15 to 17, and the U.S. dominance of MySpace is shrinking. There also has been a dramatic increase in the median number of Friends for new U.S. members, from 12 to 96—probably due to MySpace's automated Friend Finder. Some factors show little change, however, including the female majority, the 5% minority gay membership, and the approximately 50% private profiles. In addition, there has been an increase in the proportion of Latino/Hispanic U.S. members, suggesting a shifting ethnic profile. Overall, MySpace has surprisingly stable membership demographics and is apparently maintaining its primary youth appeal, perhaps because of its music orientation.