I've been suggesting for some time that Wikipedia, or some fork of Wikipedia, should allow users to "sign off" on a version of an article, and then lock that article against future edits until the signer had approved them. The signing off would allow people to cite a Wikipedia article as a source that had been vetted by at least one person (with confidence in the source depending on that person's credentials). The signer's identity (and sometimes, their credentials) could be confirmed using several methods, such as verifying an .edu e-mail address. Users could still submit edits, but they would have to be approved by the article verifier. Different users could sign off on different versions of the same article, and readers would still have the option of viewing the latest version of an article, with all of its unmoderated edits (which is what you're looking at on Wikipedia most of the time).
Knol, which allows users to submit articles on any topic they want, has incorporated all of the above features (adding, for example, the ability to verify authors' real names using credit cards), and gone one step further by allowing users to place AdSense ads in their articles. However, there's one stumbling block to Knol incorporating all of Wikipedia's content and blessing it with the verification of credentialed experts: Currently, although you have to dig a bit deep to find this out, Knol's Terms of Service do not allow content to be copied from Wikipedia.
Content on Wikipedia is published under the GNU Free Documentation License -- when you click any of the "edit" links in a Wikipedia article and begin typing in new content, you're agreeing to submit your content under the terms of the GFDL. When you publish on Knol, on the other hand, your options are to publish under a Creative Commons Attribution 3.0 License (CC-BY), a Creative Commons Attribution-Noncommercial 3.0 License (CC-BY-NC), or a traditional "All Rights Reserved" copyright model. Both the GFDL and the Creative Commons Attribution licenses are popular with content creators who want to give content altruistically "to the world" -- these licenses all allow content to be redistributed freely without modification. The main difference is in the rights that they grant to people who want to create derivative works (modifying or expanding on the original work).
The GFDL is intended as a "viral" license -- if you take a work that is published under the GFDL, and publish a derivative work created from that, your derivative work must also be published under the terms of the GFDL -- that is, also allowing other users to redistribute your work freely and create derivative works from it as well. If a site mirrors Wikipedia articles without including the terms of the GFDL, Wikipedia encourages users to send notifications to those sites pointing out that they're violating Wikipedia's copyright, and if necessary to escalate the matter to their Web hosting provider for noncompliance. You can mirror Wikipedia all you want, and even put put ads all over your mirror site, but you cannot change the terms.
Creative Commons Attribution (CC-BY) licenses, on the other hand, allow users to create derivative works and publish them under almost any terms they want, including an "All rights reserved" model, provided that they give attribution to the author of the original work. If Susan publishes an article under CC-BY, you can create a derivative work by expanding on her article, and -- assuming your contributions are substantial enough to be copyrightable in themselves -- you can prohibit other users from redistributing your article or creating derivative works from it, something that would not be possible if Susan had published her article under the GFDL. (Obviously, you cannot prohibit others from redistributing Susan's article or creating their own derivative works from it, but you can restrict these rights as applied to your own derivative work.)
Russell Potter, a Professor of English at Rhode Island College and a Citizendium contributor who explained this difference to me, points out that CC-BY licenses are more friendly to academics who want to reuse content in a published book or in a conference presentation. "Say an academic (me) contributes a long article on London's Crystal Palace," he wrote. "Others edit it in modest ways, but the article is still about 90% my own work. Perhaps I want to give a paper at a conference based on this entry, or use large bits of it in a book I'm writing. GFDL would have made either impossible." (Impossible, that is, unless the book publisher released the book under the GFDL, but most book publishing companies are reluctant to do that.)
And therein lies the logical incompatibility between the GFDL and the CC-BY publishing options currently allowed by Knol. If you copy GFDL-licensed content from Wikipedia, you are agreeing that for any copies or derivative works that you create, you will not only permit other users to remix them, but that you will require those other users to agree to the same terms for the remixed works that they publish. If you published such content on Knol under the CC-BY option, you would be granting the reader permission to incorporate the work into their own derivative work which they could then publish under an All Rights Reserved license. And the GFDL doesn't allow you to grant that permission to the reader. Section 5.5 of Knol's Terms of Service explicitly states that GFDL content cannot be re-published under a CC-BY license, and Mike Linksvayer makes this point on the Creative Commons blog as well. Some authors have begun copying Wikipedia content to Knol anyway, and even though that particular article included a link to the GFDL, users have pointed out in the comments that it's still a TOS violation anyway. Google appears to be lax about policing these violations for now, but in the right-hand column, the links to "Similar Content on the Web" show that Google can trivially detect if content is copied from other sites, and may be planning to remove such content or demote it in search results if it's copied from a site like Wikipedia that doesn't allow copying under Knol's terms.
However, the Creative Commons family of licenses also includes the Creative Commons Attribution-Share Alike License (CC-BY-SA), which is written in the same spirit as the GFDL -- if a work is released under CC-BY-SA, any published derivative works created from that work must also be released under the same license. In fact the Free Software Foundation, which writes new versions of the GFDL, announced in December 2007 their intention to make the next version of the GFDL explicitly compatible with CC-BY-SA, so that any work published under the GFDL can be incorporated into a work published under CC-BY-SA, and vice versa. This new version of the GFDL has not been released yet, but the FSF replied by e-mail to say they're working on it.
(Perhaps you might be wondering, as I did, how already-existing content on Wikipedia can be said to be "licensed" under a new version of the GFDL when it comes out. How can past Wikipedia contributors have agreed to a future version of the license that didn't exist yet? The answer is that when you submit edits on Wikipedia, you're agreeing to submit your edits under the "GNU Free Documentation License, Version 1.2 or any later version", and it's the "or any later version" that means contributors are deemed to have agreed to the next version of the GFDL, which will presumably be CC-BY-SA-compatible.)
If Google Knol adds the ability to publish under a Creative Commons Attribution-Share Alike license, and the FSF releases a new version of the GFDL that is compatible with this license, then I think we will finally see what I hoped for in February 2008 -- a "gold rush" of users copying content from Wikipedia to Knol, where it can be verified by credentialed users and protected against vandalism. Some users' verifications will be more valuable than others -- a physics article verified by a physics professor is more trustworthy than the same article verified by an anonymous user, and even an article about The X-Files may be more trustworthy when it's verified by a physics professor, not because it's the professor's area of expertise, but because a professor with a valued reputation would be less likely to sign their name to unverified garbage.
Will Knol add the Share Alike option? Perhaps they may be nervous about what would happen if they allowed unlimited copying from Wikipedia, especially with financial incentives. At the moment, Knol seems to be downplaying the fact that you can make money from writing articles, even as everyone else buzzes about it. On their front page, under "Learn More", Knol lists the reasons you should contribute: "Visibility - We value and promote authorship. Great content will be visible on any search engine. Community - You can connect with other experts in your area of interest to share and grow knowledge," etc. Really? That's all? AdSense isn't mentioned in the FAQ, and only briefly at the end of a posting about "Knol bugs and workarounds". And officially the site never mentions Wikipedia at all, except in the knols about it.
But many of the articles on Wikipedia -- especially the kind of articles that academics would be willing to sign their names to -- would probably enhance the Knol site, not drag it down. Wikipedia founder Jimmy Wales correctly predicted that Knol would generate a lot of articles about Viagra. If Knol can tolerate that garbage (and under their own policies, there is little grounds for removing those articles, unless the authors lifted the content from some other site), they should welcome the addition of articles about stochiometry, Shakespeare, and Serbia, even if they were copied from Wikipedia and then vetted by a university professor or journalist. (None of those topics have their own Knol yet, although there was room for Knols about Simon Cowell, Superman, and sex addiction.)
After all, the incentives that AdSense creates for Knol writers are roughly the same as the incentives for Web publishers in general -- you can try to turn a quick buck, or you can invest in your site's reputation for the long run -- and while there is a new "made-for-AdSense" site born every minute, few would disagree that the rise of AdSense has been good for content on the Web in general.
While copying from Wikipedia to Knol is against the rules right now, there's no reason in principle to be against creating a Wikipedia sub-fork on Knol, if Google allows Knol writers to select the Creative Commons Attribution-Share Alike publishing option. One user, responding to the unauthorized use of Wikipedia articles, posted in the Knol users' group on Google Groups: "What I REALLY want to see Google do is crack down on these clowns who are copying and pasting articles from Wikipedia." I say, just change the rules and send in the clowns.
Slashdot welcomes original submissions; many thanks to Bennett for this one.