One of the most remarkable cultural phenomena that blossomed in the Web 2.0 era are the social networking sites, such as Facebook, MySpace, Friendster, Bebo, Netlog or LinkedIn. The introduction of new communication channels facilitates interactive information sharing and collaboration between various actors over social networking sites. These actors, i.e. the providers and the users, do not always fit in the traditional communications models. In this paper we are going to examine how the new reality, realised via social networking sites, fits in the existing European legal framework on data protection. We are further going to discuss some specific data protection issues, focusing on the role of the relevant actors, using the example of photo tagging.