Hi jotrys - I hesitate to guess as its been a couple of years since we were actively building website for clients, but our experience was that the Drupal sites always ended up costing more to build the Joomla or Wordpress sites. Drupal had higher-end customers with more needs and deeper pockets.

Hi Esses - yes, you may be right. Wordpress might just be too easy for live training classes to have much traction. I've heard quite a lot of customers of commercial CMS customers complain that they're getting gouged ... the harder the CMS is to learn, the more money the CMS vendor makes. The extra difficulty of using Joomla and Drupal does add to the cost.