Hi, I've used WordPress as a content management system for small sites (not blogs) and it works extremely well. I just use pages with urls: %postname%.
I'd love to use it for larger sites too but it sounds like there will be problems once the number of pages increases if using %postname% for urls, which is what I prefer to do (see http://wordpress.org/support/topic/420032).
If this was fixed it seems to me that WordPress would be totally awesome as a cms so I would like to suggest this as a feature.
What do you think?