Knol platform has around 250,000 knols at the moment. My estimate is that the number will go up to 1,000,000 by end of the second year that is 31st July 2010. The million knol portfolio would also give one million page views per day and knol will become a top 100 website. The momentum is already there. Everyday new authors are signing up and new knols are appearing.
There are still many gaps in various subjects for writing knols. One can visit the knol to have an idea of some areas requiring knols.