We currently use MySource Matrix CMS for large projects, Wordpress CMS for small projects and Zend Framework for bespoke applications...
I'm not trying to confuse and compare a CMS to a framework, that has been done before :-)
I want to identify a few CMSs for review that have foundations in strong (preferably independent) PHP frameworks.
The only one I have looked at is SilverStripe CMS and Sapphire Framework.
We have many clients that have a CMS for internet and/ or extranet and then various other bespoke applications that are then integrated via various means to look like they're in the CMS.
I believe it will be more productive and beneficial to have a common framework between these branches so they can be natively merged.
Hope this makes sense.
PS. I have used custom assets in MySource Matrix and specific modules in other CMS but you feel you are working for the CMS not the application you are building.