According to water&stone, WordPress, Drupal, and Joomla continue to dominate open source market in 2011 with WordPress clearly leading.
Survey looked at downloads, installations and third-party support.
Downloads a week
- WordPress: 640,000
- Joomla: 86,000
- Drupal: 23,000
Download numbers are really not that accurate, because there are checkouts from repositories and web hosts' one click installs.
Alexa One Million
- WordPress: 53.6%
- Joomla: 9.6%
- Drupal: 6.4%
- WordPress: 4.2 million
- Joomla: 1.7 million
- Drupal: 308,000
Books in Print
- WordPress: 83 books, 23 released in 2011
- Drupal: 64 books, 22 released in 2011
- Joomla: 65 books, 13 released in 2011
It's interesting that Drupal books new releases are so close to WordPress. Maybe that tells about active developer community?