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If there's no time for argument over the facts before the news cycle ends, Newmark believes there's a way to post the most trusted information immediately. He hints that Shardanand's start-up may be looking at software that places different levels of "confidence" in articles, based on the author's reputation. It's an unproven idea, but that doesn't mean it's impossible. It could be a user-voting system (like eBay's ratings); a method based on the most-linked-to people (like Google News, except for individuals); or an approach that uses collaborative filtering, sending a user a "liberal" or "conservative" version of a story based on the articles she's chosen before (like TiVo and Firefly).

No matter how good software is at ferreting out the truth, though, coordinated, one-sided attacks will be a major problem. If, say, a right-wing televangelist instructs his minions to go forth as citizen journalists and lay down an extreme agenda, there's nothing to prevent them from taking over entire sites.

Wikipedia faced the issue last fall, when an edit war between George W. Bush and John Kerry supporters over their wiki pages culminated in the replacement of a Bush photo with a picture of Hitler. Both pages were locked down for several days during the 2004 campaign. Around the same time, Bush administration talking points showed up as "arguments" in a Craigslist political forum.

Newmark is focused on the challenge: "I need to figure out: How do I encourage people to work together to figure out how to prevent and fix disinformation attacks?" he asks aloud. "This is a big issue. I'm thinking I need to corral Jimmy Brooks from FactCheck, the folks I know at eBay, focus on getting to know big names at Yahoo!, Google, maybe MSN ... these are all acts in progress."

If Newmark, or one of the projects he's working with, jumps through all the technical hoops, contributors will only be able to take things so far. The shortcomings of the mainstream media that Newmark gripes about -- not investigating weapons of mass destruction claims or malfeasance by Halliburton -- aren't likely to be fixed by citizen reporters. "When you get into investigative journalism, you very quickly outstrip the ability of citizen journalists to gain access, maintain focus, and invest in a story," says Cauthorn, whose nascent company aims to enable a hybrid between citizen reporters and professional news outlets. The "social need for investigative journalists" is one of Newmark's main concerns, and he's considering making grants to the Center for Investigative Reporting. However, writing critically about powerful figures requires institutional backing, not just time and money.

Citizen journalism may become a helpful supplement to mainstream reporting, especially in smaller towns, just as bloggers help elucidate news on specific topics for millions of readers. But the more important (and more challenging) the stories are, the more likely it is that citizen journalists won't have the wherewithal to complete them. "Citizen journalism will not be the Fourth Estate," Cauthorn says. "It's not going to sit down and stare across the room at an army of lawyers for some government official who's outraged that you've written about his misdeeds."

In the best case, Newmark is joining a movement that will someday be of moderate help to the mainstream media. In the worst case, citizen journalism's optimistic supporters, in neglecting the problems of the public institution that is the mainstream press, may leave America with both a failing news media and a mediocre technology that offers little assistance on essential stories.

Even as he makes big waves in the media industry, Newmark still isn't sure this is a battle he wants to fight. "I don't want to disrupt the people who are really getting it done. I may just wind up promoting their work, I'm not sure. I could screw things up if I'm not careful," he says. "I'm speaking from the gut here, but the deal is, I'm trying. And sometimes, trying and making noise means something."