Definitely avoid Joomla if you can. I've been maintaining a Joomla site since 2009, and I can't update any of the core components because it would break too many plugins for which there are no newer, compatible versions.
I'm building a replacement for that site right now using Rails. If that's not an option, go with Wordpress.
I'm building a replacement for that site right now using Rails. If that's not an option, go with Wordpress.