I stumbled across a CMS system yesterday (literally Stumbled, as in I found the link via a site using stumbleupon.com). It is called MODx and is touted as an Ajax CMS and PHP Application Framework. Digging deeper, though, revealed that it is supposedly also search engine friendly, with se friendly URLs and the ability to handle unique titles and meta data.
I haven't tried it yet, but it does appear to be easy to use, on the surface at least. It looks as though you use whatever code you want for the template, and then just throw in a few tags here in there to handle titles, meta data, etc. Similar to how WordPress works, but with you controlling the template more completely.
I don't currently have a project going where I would need this, but I'll keep it in mind to try out during a future project. If anyone has tried it, please comment on what you think of it. Search engine friendly CMS's are still a rare commodity, and even rarer still, if they are easy to use. Anyone use it yet?