Like Yahoo! Answers, Wikipedia isn't perfect. But for savvy browsers who know how to use it, Wikipedia is an invaluable source of factual information. In the last two years, there's been a heated debate over whether Wikipedia is as trustworthy as Encyclopedia Britannica. This obscures a crucial point: Wikipedia is at least reliable enough that such a question can be asked. Take my word for it—no one is going to make any such claims about Yahoo! Answers any time soon.
Wikipedia's greatest virtue is that it is self-editing and self-correcting. The site's draconian efforts to consolidate pages and remove entries that aren't deemed important have a crucial side effect: They focus users' energy on revision rather than addition. By contrast, Yahoo! Answers is more devoted to quantity than quality. It struggles to prevent repeat questions from appearing over and over again. And unlike Wikipedia, the Yahoo! community expends far less energy trying to hide dubious or just plain incorrect contributions, despite a community rating system designed to flag them. Often, a correct answer will be hiding somewhere on an Answers page, only to be obscured by a tide of wrong or off-topic material that never gets erased. Wikipedia pages are subject to constant revision. If a vandal screws with an entry, one of the site's busy janitors cleans it up. If new information becomes available or a new user devotes energy to making improvements, then a Wikipedia article will get better even years after it's first posted. Yahoo!, by contrast, "closes" questions to new answers after a week, although users occasionally post comments afterward. While the site's answers live forever on the Web, each question attracts only seven days' worth of collective wisdom.
The small, almost obsessive community that built Wikipedia created a culture of reliability. For contributors to see their writing on the site, they must submit information that's clear and accurate enough to survive the scrutiny of other users. Yahoo! Answers has created a more formal, yet far less successful, reward structure to identify top users. Every time you post an answer, you earn two points. If you win a "best answer" distinction, you get 10 points. (The person who asked the question gets the opportunity to select the best answer; if they choose not to, it is selected by community vote.) This system highlights the site's greatest strength and its greatest weakness: Everyone gets credit for answering, but there's not a huge push to make sure the answers are right.
As its devotees would point out, Yahoo! Answers allows you to ask questions Wikipedia would never touch. Many of the site's users are simply looking for advice, local knowledge (like a restaurant recommendation), or an opportunity to start a discussion. But for these questions, too, the quality of the responses varies widely, and users can be stuck struggling to separate the good answers from the bad.
Even though Yahoo! Answers is so frequently sloppy and inaccurate, it's still the juggernaut in its field. Despite a rapid proliferation of answer-giving sites—Amazon.com's recently inaugurated Askville just joined a crowded field that includes Answerbag, WikiAnswers, AnswerBank, and Ask Metafilter—Yahoo!'s is still by far the most popular. And in the question-answering game, size matters. While the others have a few clever features (like Answerbag's efforts to separate "educational" and "conversational" questions) or a more specialized community, the sheer magnitude of Yahoo!'s community gives it the upper hand.
After all, while Yahoo! Answers and its peers are classified as reference tools, what they actually provide is social networking. The thrill of Yahoo! Answers comes in the instant interaction: the scores of questions, the immediate back-and-forth discussions, the opportunity to feel like an expert, and, eventually, the promise a query will be labeled a "Resolved Question" no matter how difficult.
For a passive reader, this has the same value as listening to two random guys at a bar talk about what to do if you are driving during a tornado. You may not learn very much by eavesdropping—and you certainly shouldn't trust what you hear if disaster strikes—but that isn't really the purpose. The lesson Yahoo! Answers teaches is that, for millions of people on the Web, it's less important to get a good answer than to get someone to listen to your question in the first place.