The two fundamental differences on Open Source CMS
As we mentioned before, a Open Source CMS is not free in any way. What divide the Open Source CMS market in two is whether there is a professional vendor behind a system or not. This is not only a fact for Open Source CMSes, but for all type of Open Source applications. You can choose between systems like Alfresco and eZ publish that work with professional companies as vendors, or you can choose systems like Joomla! and Drupal, which rely on a community or independent development companies to provide all the development and support.
Companies that expect support and other services that traditional software vendors offer, should look for a commercial Open Source CMS vendor. However it is normal to experience that Open Source CMS developed by a commercial Open Source CMS vendor do not adapt to new technologies as fast as the community driven CMS solutions. This delay is often due to commitments and guaranties for commercial clients. Therefore commercial Open Source CMS vendors are considered to be slower, but more stable in comparison to community driven alternatives.