StudiVZ claims to have 10 million active members, and is the largest social network in the German-speaking world, covering Germany, Belgium, Austria and Switzerland. The network is actually comprised of three different sites, each one a separate social network aimed at different segments of the market. StudiVZ.net is the classic site for college-aged students, SchuelerVZ.net is for high school students and MeinVZ.net is for older adults (these three networks were very hard to decipher in German when I attempted to sign up).
The VZ networks are largely financed by advertising. We generate additional revenue through the participation in partner offers (eg via apps).