One of the most exciting evolutions in the internet over the last years is the spread of social networks. No other genre of web services has such high expansion rates like the social networking sphere. MySpace, LinkedIn, Orkut or Facebook have gained enormous popularity over the past years because of a steadily increasing demand for communication and collaboration among users. Forced by the fast evolution of the internet, innovative web technologies and networking functionalities, the user changed from a passive information consumer to an active content producer and distributor. As a key success factor, social networking services offer modern communication possibilities for people by supporting user interaction and data interchange. This paper presents a snapshot of the social networking sphere attained by an extensive site analysis. As a main focus, current trends, key functionalities and revenue models of successful social networks were identified and analyzed in detail. To contribute to the development of successful next generation social networks and web services, the presented trend-setting movements are crucial for meeting the demands of modern users.