Knol is Google's attempt to match the success of Wikipedia. The beta version launched yesterday with Google welcoming all contributions.

Some of the differences between Knol and Wikipedia is that articles on certain subject areas (or knols) are written by named experts, whether they leave their articles open to edit by others like wikis or moderated is up to them. Rather than appear in single website, articles will appear as single web pages which Google believe will improve search.

More of the story at ZDNET.