If you want to know contemporary left thinking about social change, and how it takes into account the commons, then this is a quite extraordinary video.
It features three speakers:
1) Alex Callinicos, who in my view expounds the classic left view based on the primacy of struggle
2) Slavoy Zizek who really rocks here, despite his nervous ticks
3) John Holloway who expounds the interstititial approach of using the cracks in the dominant system to create new social relations, and how to increase confluence amongst them
My own take is that the p2p approach combines John Holloway, but without forgetting the key issue of power and struggle, as expounded by the first two speakers. It is the combination of the constructive approach, and the mass mobilization of social movements, that will bring about systemic change.