In 1728, Ephraim Chambers, a mapmaker in London, published the Cyclopaedia -- the first encyclopedia to include cross references. Almost 275 years later, Wikipedia, the online, user-created encyclopedia, is championed for its volunteer model and its elaborate system of cross-referencing and verifications. But the Wikipedia model has had a rough couple of weeks -- ever since the mainstream media jumped on the story of Robert F. Kennedy confidante John Seigenthaler's outrage at false information posted in his Wikipedia entry.

The concept of Wikipedia -- and the general idea of "wikis," or user-edited Web pages -- is notable because it embodies one of the key cultural movements of the decade. Called Web 2.0, it's the notion that the Internet should be fueled by user-generated content -- blogs, wikis, podcasts, and user-created add-ons to programs such as Google Maps and Firefox. The desire of people to contribute online content is as old as the medium itself; now software improvements and broadband adoption make it easier than ever. With the tools for content creation in the hands of single individuals, not just companies and institutions, Web 2.0 means a more democratic Internet, and a truer voice, or at least a broader one.

"When people think of Web 2.0, they're thinking of Wikipedia," says Larry Sanger, a co-founder of Wikipedia, who's no longer with the enterprise and currently involved in a new online encyclopedia project.

But the Web 2.0 concept, and Wikipedia itself, still have some growing up to do. In part because of the Seigenthaler flap, Wikipedia is going through a very public coming-of-age. "The last two weeks, it's been hard to get any work done," says Jimmy Wales, founder of Wikipedia and president of the non-profit Wikimedia Foundation.

At the heart of the issue is a problem that many startups would kill to have: overwhelming interest in their product. In 2001, Sanger predicted that, with a little luck, Wikipedia would have 80,000 articles by 2008. The site currently has more than 850,000 in English alone. Throw in 200 other world languages, and the total rises to 3.7 million.

Wikipedia was founded with a radical premise: thousands of enthusiastic volunteers would scan the entries regularly, ensuring that they remained truthful -- or at least not erroneous for very long. In addition to being reviewed by the general public, Wikipedia articles would also be vetted by administrators and "page watchers."

That's exactly what has come about. But with the huge proliferation of Wikipedia entries, as well as the built-in ability for anyone to contribute to the site, the occasional vandal has appeared -- and gone undetected for too long.