I lived in Barcelona for 7 years, during the spanish protest knowk as "indignados". During those excinting days every neighbour of the city was trying to organize in a different way. There were meeting every week to talk about the real neighbour problems and to try to offer a solution. I don't know if the entire process has gone further or not but it was a very new experience top partecipate to some of those meeting. Maybe in a place so huge like London is it would be mpore difficult to pull the poepole out of their business to join meetings like thos ones. But I am pretty sure that using the technology, doing it online, it would be possible. For some issues people have much clearer view than city government.