One source of confusion is that there are two different definitions of CMS running around. The first is more literal, where pieces of content are managed as content separated from form or design. In this sense, every WordPress installation, blog or not, is a CMS. Most blogs in general, unless each entry's design is hand-coded, are instances of a CMS.

The second definition, which a lot of recent wordcamps have gotten at, is operational. WordPress as a CMS is being taken to mean a larger installation that is not centered around a reverse-chronological blog. This usually involves a greater variety of moving parts: a larger entity or organization than one blogger, more types of pages along a continuum from fixed to dynamic, a theme friendly to menus and maybe more plugins/widgets, and more end users than the web designer. There are already many solutions to changing the admin interfaces for various user roles so that some of them don't necessarily have to see the word "blog."

Note that this is much more than "WordPress, Debloggified." Either a blog or posts reused as "articles" often remain in this second use/definition.

The phrase "content management system" is a mouthful of awkward, but hard to replace. Sites like cmswire, cmsreport, cmsmyth, cmswatch, and cms critic really do like to talk about WordPress. We should be glad that we're talking about WordPress and not "WordBlog."