I'm pretty much in the group with everyone else here with regards to WordPress. It's probably one of the easiest blogging tools I've worked with.

Joomla is much more designed for content management and design. It's a great tool as a portal script (similar to what PHPNuke was back in the day). While you could use it for publishing articles etc, I'd personally go back to WordPress for that.

They both have their own focus, and as a publishing tool, Joomla is hard to beat. As a blogging script, Wordpress beats all others pretty much.