A few months ago no one had heard of "podcasting," because it didn't exist. Last summer an MTV veejay turned technophile named Adam Curry wanted to do an Internet-based radio show, distributing it through his Weblog. (A Weblog, or blog, is a personal Web site where somebody self-publishes an electronic journal, often linking to other things on the Web that strike the author's fancy.) With the help of fellow bloggers, he created special software that allowed digital audio content to be distributed directly to an iPod digital music player. You could even "subscribe" to these audio feeds, automatically loading up your little gizmo with these "podcasts."

Something as interesting as podcasting was bound to be embraced by the blogosphere, the interconnected tapestry of hundreds of thousands of Weblogs. In specific slices of the sphere, opinion can be shaped by a much smaller number. By dint of reputation, novelty and charm, certain "alpha bloggers" have built large and influential audiences.

The bloggers who follow technology consist of a particularly evolved community. The alphas, or "A-listers," as they call themselves, commonly cross-link to one another, with the effect of having one of their comments amplified and commented on. In the case of podcasting, the accumulated buzz from the blogs became deafening. The subject suddenly became the hot topic in geekdom, and soon appeared in The New York Times and BusinessWeek.

The lesson is that there's a new force--spearheaded by people who work for no bosses and whose prose never sees an editor's pencil--that provides the water-cooler fodder for the larger high-tech community. Its power extends not only to high-tech cool-hunting but also to what's politically correct, geek style. (Open source... gooood. Onerous copy protection... eeeevil.) And the significance of this phenomenon has some important implications for the way opinions will be formed in the decentralized world of Internet media.

Let's consider the tech bloggers who make up the A-list. No one hired them. No one appointed them. All you need to start your own Weblog is some cheap software tools and something to say. Out of the inchoate chatter of the Web, the sharpest voices simply emerge. Certainly there are those--like Dave Winer, an early proponent who just completed a yearlong stint organizing a blog community at Harvard--whose reputation preceded them into the blogosphere. But more common are the people like Linux Journal editor Doc Searles, a long-respected tech observer whose well-read blog has made him a virtual brand, or Dan Gillmor, whose "We the Media" book is the blogging manifesto.

Other people, by a combination of writing skills, unyielding curiosity, canny instinct and lots of sweat equity, rise up from total obscurity to join the big dogs in the community. This happens when an A-lister notices a newbie's work and links to it. In those cases fame can come fast. Just ask Robert Scoble, an unknown when his items were first picked up by the alphas. "Within two weeks I was invited to Steve Wozniak's Super Bowl party," he says.

"There indeed is an A-list, as well as important niche influencers on smaller topics," says Dave Sifry, CEO of Technorati, a company that tracks the blogosphere. Sifry keeps a running list of them, a geek hit parade of power brokers who zing arrows and shape opinions while quaffing lattes and using the Starbucks Wi-Fi. In the tech conferences you can often spot them in person, clustering toward the wall so they can keep their laptops plugged in. No matter where they are, they maintain a running conversation with their unseen audience, which can be as big as 20,000 visitors on a good day. And though no one pays for access to their homegrown publications, they can shape opinions, as the podcast example shows. "The blogosphere is a tipping-point machine," says Searles, referring to Malcolm Gladwell's treatise on how ideas and trends can suddenly tilt from obscurity to ubiquity. A good idea gets amplified by the "echo chamber" of the blogosphere. It need not be the original thought of the blogger. In fact, as scientists from the HP Information Dynamics Lab wrote in a paper titled "Implicit Structure and the Dynamics of Blogspace," ideas move on the blogosphere like viruses; the alpha bloggers spread concepts like Typhoid Marys.

In order to crack into the upper strata, you have to post frequently to stay on the fickle radar of this ADD-infested crowd. You have to link prodigiously to other blogs, increasing your profile and increasing the chances for inbound links. And you must hold strong opinions about what you're writing about--passion is required in a good blog. All of this takes time: Scoble spends two hours daily writing his Weblog and three more hours reading hundreds of other blogs in search of fresh ideas and nifty software innovations. "I want to be the first guy to spot the smart new guy or a cool new Windows app," he says. Even then you have no guarantee of blog fame.

And what do the alpha bloggers get in return? Certainly not riches. Though it's possible to pick up a few hundred dollars if you enlist in the program that carries Google's ad on your site, many A-listers don't bother. "If you're into blogs to make money, you're into it for the wrong reasons," says Searles. "Do you ask your back porch what its business plan is?" On the other hand, some alpha bloggers report better jobs, more lucrative consulting, speaking gigs and--if not groupies--a certain bit of glamour that comes from having people hang on your every word at the end-of-day reception at a tech conference.

But don't expect the alphas to become the establishment. Before that happens, the unwashed blogging hoi polloi will shame the A-listers back into maverickville--or take their places. "People come out of nowhere and get discovered," says Scoble. "Suddenly they have 4,000 readers a day." Who will be the one who discovers what comes next after podcasting?