The definition of what a certain config-file format looks like (referred to in the article as metadata) should (naturally) be stored in separate files for each, so that people could create and distribute these format definitions in a simple way.
I'd say that for a system like this to ever grow popular, it needs to be heavily based on the "plugin view" in general. Creating new plugs/defs should require no awkward object file compilation etc.
On projects like this, BLOAT is alway waiting just around the corner; A good design would enable features such as "History Log" thorough a simple RCS-plugin.
This package simply kicks ass.