Main point here is what PHPFusion is not a CMS(Content Management System), but CMF(Content Management Framework). Based on following articles on Wikipedia about what is CMS and what is CMF, it becomes clear what CMS is not a whole system(like PHPFusion, Drupal, Joomla), but a system like "Articles", "Custom Pages", "Downloads", "FAQs" etc. while CMF is a system like PHPFusion, Drupal, Joomla. Here is list of CMF's in which you can find similar to PHPFusion by purpose systems like Drupal and Joomla. The real CMS whiteout CMF is something like this, this is a CMS because its a system designed to manage only one type of content, Articles.
I don't know about Wordpress, but many so called "CMS" is not a CMS. * Many developers not trying to understand difference between CMS and CMF. * Many current CMF's was started as CMS for private usage, designed to manage one single content type, then creator decided to make it public, he added more features including new content managing ways, but did not changed name from CMS to CMF. For that reason there are so many so called CMS, but in reality even half of them is not a CMS.