User managed trust in Social Networking - comparing Facebook, My Space and Linkedin

Social Networks is the highest growing web-application in terms of users. Different surveys show that users are most concerned with their privacy in respect to web-based social networks. Anyhow, uses "compete" in the number of "friends" they can attach to their own profile. This means that the trust relations users are using to establish friends in the web applications becomes significantly different from the trust relations used in face-to-face meetings. This paper compares and discusses some of the existing self-management mechanisms in trust in three of the most used internet based social networking applications and suggests different aspects for dealing with trust from a user-centric design perspective.