Over the last few months, Digg has emerged as one of the biggest forces shaping Web traffic. The participatory technology news site lets registered users post links to new Web pages and "digg" or vote for their favorite pages posted by others -- thus raising them higher in the queue for each subject category, and (for the most popular stories) onto Digg's front page.

Seemingly overnight, Digg has become a serious rival to Slashdot, Stumbleupon, Memeorandum, Delicious, and other social bookmarking/community rating/"intelligent browsing" services. Here at TechnologyReview.com, Digg is routinely among the top 20 referring domains -- meaning the sites where people find and follow links to our stories. In November, it was actually the third-ranking referrer, after Google and Yahoo, thanks largely to the hundreds of people who dugg one terrific article on aging and the brain by TR biotech editor Emily Singer.

Now Digg has unveiled some radical improvements to Digg Spy, a page that shows a scrolling list of the stories people are digging (and dissing) in real time. When you go to Digg Spy, you are essentially watching democracy in action. You'll see the new pages just submitted to Digg, the pages people have just dugg or commented upon, and also the pages they've "buried" or removed from the queue due to irrelevance or duplication. It's like being in a massive restaurant kitchen and watching which orders are up and which dishes picky diners are sending back. Pretty soon, you get a sense of what's good on the menu.

Helpfully, Digg's creators have added "pause" and "play" buttons that let you control the otherwise ceaseless scrolling; when I visited the page at 3:45 p.m. PST today, Digg Spy was adding about 50 stories per minute. Kevin Lim, an educational technology specialist at the University of Buffalo, explains all of Digg Spy's other new icons and functions in this very enlightening post.

For some great supplementary reading on Digg, check out Alex Bosworth, a blogger for the Seattle-based open source software development firm SourceLabs; he has written an interesting analysis of the dynamics of Digg, including the four main types of Digg users and ways to get stories dugg (dugged? digged?). And in a November online-only interview, Business Week talked with Digg founder and CEO Jay Adelson and co-founder and chief architect Kevin Rose. BW asked Rose what Digg does to maintain the quality of the sites appearing on its front page. The answer: very little. "The larger the critical mass of users and the collective wisdom applied to digg, the better and more relevant the stories get," Rose said.

Digg Spy reminds me of the big screen in the lobby of Google's headquarters in Mountain View, CA, which displays the search terms being submitted to Google's servers in real time. The Google Zeitgeist gives a static snapshot of trends in Google user's interests -- but it's not nearly as interesting as the display in the lobby, which, if you watch it long enough, gives you a sense that you're tapping into the wanderings of the collective human mind. Digg Spy does that too -- but what makes Digg's page cooler is that its shows you how people rate content they have already digested, while the Google display simply shows which topics people are curious about. Check it out. You might even see a Technology Review story scroll by.