The problem with most frameworks is that they’re all or nothing. Some good ones, TurboGears and Symfony come to mind, take existing projects, which makes it easier to swap stuff out, but you’re still on your own.
Joomla seems to be going the route of adding it’s own MVC. I’d heard earlier that they were going to rebuild on CakePHP. This is going backwards, but going the other way, adding CMS to the framework is just as silly — like Zope. I don’t want to use a framework if it tells me how to develop. And I don’t want to create content in HTML unless I have to. That’s what paying users get to do.
CMS is an application, and it should only be used to manage content. Integration with authorization and the model is necessary to check permissions and generate from templates, but that’s it. If a site user needs to edit their content in the site, then an edit button should forward them to the CMS app. The site should not be run by the CMS app.
with all the cms models there is a caching system – so in effect the user is viewing a static generated html page served up as a static html page and if they want to edit it, they go to the cms