I think SNSs are under-theorised. So as I turn my attention to some of the data collected last year on teens' social networking, here's some first thoughts on the big F.....I'm suggesting that Facebook provides contexts for the social construction of relational meaning. An individual personalised profile page resources and constrains this social construction in the way in which it presents multiple invitations and a limited set of opportunities. If we take the view that identity is always dialogic and performed in relation to the other, then there is a sense in which you are called into being by your profile page. Here the process of interpellation, used by Butler (1997:5)and drawn from Althusser (1971) is helpful. Interpellation is mobilised by Butler to illustrate how people accept and internalise social relations and norms. On Facebook the busy screen that updates you on activity in your social network already positions you, but the site's prompting question 'What's on your mind?' hails you into being as a particular kind of subject, to use Butler's expression. In this process of interpellation you enter into a universe of textualized selves in which your own self-narrative is developed, modified and repeatedly performed in relation to others. Social relations and friendships are rehearsed and more or less publically enacted in a heavily mediated environment. But of course this environment intersects in complex ways with life outside Facebook - life in what we sometimes call the 'everyday world', in which freindships are also enacted, but also in life in other mediated environments and life as experienced in relation to other popular narratives.