Open Source CMS is a site worth following as it has a lot of interesting data regarding CMS and web designs. Here are two posts to follow:
CMS Market Share
WordPress has been sitting on 69% – 70% over the past months. OpenSourceCMS updates this pie chart regularly and it is interesting to see by how much WordPress dominates. WordPress is Open Source and is a great platform that ensure optimal SEO second to none. Joomla is doing well in second position and quite far off the third: Drupal. Still, if you look closely at the market shares of Joomla (10%) and Drupal (6%) you understand that WordPress offers a highly sophisticated CMS to its users.
This post compares ratings of all CMS on OpenSourceCMS. Every user is allowed to rate each CMS once. Joomla is in a top position here as well. WordPress is at a lower position. Ratings are of cause relative and depend on so many factors. Anyway, this post is interesting to follow as the content is updated regularly.