Clay Shirky is an adjunct professor at New York University and author of Here Comes Everybody: The Power of Organizing without Organizations. Read a review of his book in "It's Not a Revolution if Nobody Loses" by Emily Gould, from the September/October 2008 issue.

There are several interesting things about the Obama campaign's decision to text-message his VP announcement directly to his supporters. It makes the choice more exciting. It reinforces a direct connection with his most passionate followers. It creates an enormous list of mobile-phone numbers that the campaign will doubtless use in its get-out-the-vote efforts in November. The most interesting effect, though, is the way it cuts out mainstream news outlets.

Broadcast news has two conflicting imperatives--get the news out fast, and provide interpretive context. For most of the last century, these two things weren't in serious conflict, since radio and TV were the only ways to spread information quickly and at large scale. In that environment, the classic format for a breaking news story went like this: "Obama has announced that Batman is his VP. Now we turn to our political analyst, the Joker, to discuss what this all means ..." Because the broadcast outlets were required for the simple act of distribution, they were able to link that to the complex act of exposition.

What the Obama campaign has realized is that broadcast is no longer required for news distribution. An individual organization, with the goodwill of its users, can now run a communications operation that reaches national scale. The pitch to recipients of the text messages is access to unfiltered news the minute it happens, but the reality is that there are now going to be more filters--millions more--for this bit of news.

As a proportion of all Democrats, the obsessive ones who have signed up for Obama's text messages is tiny, but text messaging is only the first-order distribution strategy. Seconds after the VP message goes out, Facebook and MySpace and Twitter and the blogosphere are going to light up with excited rebroadcasts. This superdistribution will be instant and massive, and it has a chance of being the first way a majority of Democrats under 30 learn the name of the candidate.

By harnessing social networks to distribute the news, the Obama campaign ensures that many people will be getting it from a trusted contact who is also an Obama supporter. As a filter for the news, this is close to the Platonic ideal for any campaign communication. Even when some of his supporters dislike the choice, as they inevitably will, they will only be able to broadcast their discontent to hundreds or thousands of others, not millions, and those negative messages will be in an environment with many more positive ones.

Distribution over social networks will also undercut the ability of traditional news outlets to provide context with their content. Because there are going to be millions of outlets for the news instead of hundreds, it will probably invert the usual order of news analysis, with professional news organizations asking what Obama supporters are thinking about the choice, rather than telling them what to think.

This is the best chance the campaign has to shape the conventional wisdom to its advantage. In terms of content, the announcement may yet be a damp squib, with an uncontroversial and unsurprising choice eliciting basically the same reaction everywhere. But as an exercise in piggybacking on social networks as national media outlets, this is a watershed moment.