While not strictly a new idea, edit-in-place functionality can really expand the usability of a CMS. Normally, a CMS has a complex backend for editing content, a segregated editor screen, or buttons that have to be accounted for in the layout code. The idea here is that all output is editable (with proper permissions, of course), by merely clicking (or double-clicking) on it. Like an a local editor. These tools are not production ready, IMHO, but this guy is definitely going in the right direction, and his to-do list perfectly matches what I think needs to be fixed.

Check it out