Just installed and am in the process of configuring the ‘corePHP’ WordPress MU component for Joomla! This nifty component allows a WordPress MU install to run within a Joomla! install.
This is great, you can have a great Joomla! based site that also hosts multiple user WordPress blogs. This is pretty much exactly with these folks were looking for, and it integrates very well with the built in user management as well.
I’m still tinkering with many customizations to get this just how we need it, but most of the difficult work is already done by the component.
Also very convenient are the modules that ‘corePHP’ makes available for this component too. There’s module to display recent blogs, recent posts, etc.
Very good stuff so far.