Step aside, Wikipedia. With last night's unveiling of Knol -- the company's term for "a unit of knowledge" -- Google's (NASDAQ:GOOG) out to get you.

Why does Google need a "Wikipedia killer" in the first place? For one thing, it must pain Google to see Wikipedia pages rank so high on its own search engine. Visitors get the answers they want without having to click on any revenue-generating Google ads.

The "do no evil" side of Google keeps it from penalizing the Wikipedia pages. But that won't stop Knol from stepping in to create community-driven reference material that Google can wallpaper with its text ads.

Knol -- no relation to communications provider Knology (NASDAQ:KNOL) -- began inviting select contributors earlier this week. "Our goal is to encourage people who know a particular subject to write an authoritative article about it," reads Google's official blog entry. "The tool is still in development, and this is just the first phase of testing."

In short, Google's emphasis will be on reputable authors, instead of the anonymously scripted and perpetually reshuffled Wikipedia entries. That's definitely a lot like New York Times' (NYSE:NYT) About.com. But here, everyone will eventually be allowed to write for Knol, creating what may be a glut of repetitive information -- and a wide disparity when it comes to quality.

The pot of gold at the end of Big G's rainbow
The kicker here is that the incentives to produce useful entries will be plenty. Since Knol names names, reputations are at stake. Reader reviews and other Web 2.0 goodies should keep the articles honest. Google's seasoned algorithms will also sift through the submissions, making sure that the best entries bubble up to the surface.

Knol authors can also elect to have Google grace their entries with targeted AdWords promos -- thus giving the author a slice of the tasty revenue from those sponsored links. With the opportunity to profit from one's knowledge, Knol could be huge -- or a huge mixing bowl of useless garbage.

"Competition of ideas is a good thing," Google claims, in defense of its open-door, hands-off policies. That may be so, but a product is often only as good as its weakest hyperlink. One shoddy page, one inaccurate fact, and Knol could get messy in a hurry.

What a Wiki web we weave
Wikipedia is imperfect, but forgivably so. If someone sneaks in a third-party link to a commercial site, its self-policing community will snuff out the offending lines by the time the next set of eyeballs combs things over. There's a reason why Amazon.com's (NASDAQ:AMZN) Kindle features free access to Wikipedia entries as a perk.

Wikipedia has left a lot of money on the table by not monetizing its website beyond user contributors, but that has also given it an aura of integrity, even if visitors can never trust the actual content completely.

However, content appears to be king at Google now. It doesn't matter that other dot-com content crafters like CNET (NASDAQ:CNET), Marchex (NASDAQ:MCHX), and Internet Brands (NASDAQ:INET) are trading at pre-teen prices. Google knows how to draw a crowd, and Knol is simply inviting visiting content to play on its own home field. It's pretty brilliant, really.

Set up your folding chairs early to see this one play out. I call first dibs on the term "Knol troll" as a name for the money-chasing types who will plague the site if Google winds up encouraging mutinous behavior. 

Google expects authors to deliver quality content, because their names will grace their articles. But Google's own name will be attached to Knol, with all of its brand-broadening and brand-diminishing ramifications. So step aside, Wikipedia -- but watch where you step, Google.

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