Wikipedia’s audience continues to grow rapidly, with the collaborative encyclopedia having added around 20m monthly visitors over the past 12 months.

Figures from Nielsen/NetRatings show that Wikipedia had 46.8m unique visitors in May 2007, a 72% increase on June 2006. In addition, the site topped the news and information category every month this year.

Research earlier this year from the Pew Center for the American Life Project found that 36% of US internet users consult Wikipedia regularly. This equates to 8% of the total US population.

Wikipedia has often been criticised for the inaccuracy of its articles, which is always going to be a problem when anyone can edit entries.

One of Wikipedia’s co-founders, Larry Sanger, recently launched Citizendium, which aims to improve on the original by having more expert input.