More than 10% of all the websites in the world are run by Drupal, WordPress and Joomla

More than 10% of all the websites in the world are run by Drupal, WordPress and Joomla — just these three. And all three are open source CMSs, so if you just count those three CMSs, you would lose 10% of the websites.

Quite impressive.

http://mashable.com/2010/11/01/dries-buytaert-interview/