Wikipedia founder Jimmy Wales commented that it "is a bit early to tell" whether Knol will generate the sort of content that would make it an encyclopedia.
In the present format, it seems far more like a collaborative blogging platform that will generate lot of opinion pieces rather than encyclopedic content.
Google has to think of ways of classifying content into rated and unrated and give rating of authenticity and rating of usefulness etc. to provide assurance to readers that the information is more accurate.
One feature of Knol that provides assurance is the credentials of authors which is a must in Knol.