I would also like to give a thumbs up to
CMS Made Simple, it's a great system that is free, stable, easy for the client to work in and easy for designers to use. Once the system is installed (which is very simple), getting new templates running is as easy as regular designing - very little special code is needed, all you have to know is a bit of Smarty, but even if you're new to it the basics will be fairly obvious.
WordPress is a good system for blogging, but the template system is a hassle. I'd say the best option is to use blogging systems for blogging and CMS:s for content managing.