As competition in the social networking space heats up, the main players are beginning to refine and develop their social value propositions. In the UK Bebo and Faceparty have both recently launched similar features to myspace music with the launch of Bebo Bands and Faceparty music groups respectively. Bebo seems to have had some success with this strategy but it's ultimately these are just incremental, copy-cat feature additions.
However, Xuqa, previously a college/ university focused social network, shows the potential for more radical innovation with its recent relaunch as an "online reality game" incorpating competitions, poker tornaments and other games elements. These guys are really pushing the boundaries here with something that really differentiates the site from the competition.
As the social networking market matures this kind of non-linear innovation, involving new types of social features is going to become more and more important.