Is Content Management a solved problem?
apsurd: I think there are enough specific end-user needs to justify tons of specific CMS instances. It's funny to me how much wordpress is hacked up in order to try and accommodate more business oriented clients. I think tons of freelancers sell their clients hacked wordpress  sites because it gives their clients CMS access, even if all they are doing is "updating a blog post".A CMS is just a tool, not a solution. So rather than asking if CMS is a solved problem I think a better approach would be asking what problems need which kind of CMS and building from there.