I've been thinking about user generated content through the framework of exchange, and exploring the ways in which the different 'economies' of exchange interact within some social networking sites(eg. information, economic, social or affective, and reputation exchanges). It's interesting to look at motivations across a broad range of exchanges and how these may be interlinked in quite complex ways. I've written a conference paper about it available at http://eprints.qut.edu.au/26455/ Cheers Sal Dr Sal Humphreys Media Studies The University of Adelaide, AUSTRALIA 5005 Ph : +61 8 8303 5227 Fax : +61 8 8303 5241 e-mail: sal.humphreys@adelaide.edu.au http:www.salhumphreys.org