Quinn Norton reports in depth on Wired with a careful, important account of where Anonymous's actions come from -- how coordinated activity (political, lulzy, legal and illegal) can emerge from noise, randomness, bombast and joking. This is the best description of how decision-making works in decentralized movements, and has important implications for the future of activism, governance, politics, crime and security:

But it’s a mistake to identify Anonymous entirely with these arrestees, some of whom were blackhats and others who were guilty of just using the LOIC. The hacks draw their power from the support of the wider collective, not the other way around. The majority of Anonymous operations are conceived and planned in a chaotic and open fashion. At any given time, a few thousand people are congregating on the Anonymous IRC channels, figuring out for themselves what it means to be an anon. And together they embody whatever Anonymous is going to be that day.

Most of the time, in most of the channels, there’s little more than conversation; sometimes a whole channel will consist of lurkers, with no one contributing a thing. But when some offense to the net is detected, anons will converge on one or more of these “chans,” with hundreds or thousands arriving within hours—many of them new to Anonymous and yet all primed and eager to respond. What looks in one moment like a sad, empty chat room can quickly become the staging ground for a major multipronged assault.

Consider OpBART, which flared up in August 2011 and dealt with an unlikely issue for Anonymous: the messy offline world of race relations and police violence. Ever since 2009, when a Bay Area Rapid Transit police officer shot and killed an unarmed black man named Oscar Grant, protests against abuse of authority by transit police had grown. On August 11, anti-BART activists were planning a rally at several of San Francisco’s underground transit stops to protest another shooting by a BART officer, this one of a homeless man named Charles Hill. It was an unremarkable story by the standards of the national media, but the response from BART to the planned protest did catch the interest of the local press: To thwart protesters from coordinating via mobile devices, BART cut cell service at its downtown stations.

How Anonymous Picks Targets, Launches Attacks, and Takes Powerful Organizations Down