Knol is closing down

Google's four year experiment called Knol (unit of knowledge) is being taken out of service on May 1, 2012. This is just one of several projects Google is shutting down. Knol was launched in 2007 as platform which allowed users to write their own articles and receive comments and suggestions from others. Some thought it might be a strong competitor of Wikipedia since it replaced anonymity with authority in the publishing space, but that has certainly not happened.

Google has coordinated with Annotum to allow users to migrate their content out of Knol, but I'm curious how many articles will be lost permanently because of inaction. Knol has a robots.txt file that prohibits web crawlers from crawling their site, so I presume that none of the Knols are archived by the Internet Archive.

I wrote my first and only knol about search engines back in Feb 2009. Instead of migrating my article to Annotum, I have saved it to my own website.