Economic models of interaction improving a sustainable city

The paper explores three dimensions: a) The utility to develop loops based on Web 2.0 arrangements in order to collect new sets of data to improve life and governance of huge metropolis like Shanghai ; b) The new models of economic sustainability be it in market oriented transactions or in public sphere involve from now on collective intelligence, prosumers but also open source and peer to peer production, all the forms of wiki contribution and participation in a urban context ; c) Public administration and urban governance are confronted to a new crisis of scissors: huge needs in funding to face new spending and difficulty in raising taxes. Economic models of social networks may provide better governance and a crowd financing through crowd sourcing.