[jasomill]

The difficulty here is to ensure said interface doesn't make trivial changes to the flat files. Emacs has this down. As a counterexample, Visual Studio 2010 stores its settings in an XML file that, after pretty-printing, is quite human-readable. But, formatting aside, VS tends to reorder elements in this file even when you don't change anything, making sensible source control unnecessarily difficult. The somewhat manual workaround is to store important settings in a well-formatted settings file and use this as what VS calls "team" settings, because the IDE doesn't write or rewrite team settings files; this is also a nice solution because you probably don't want to sync things like window sizes and positions between a desktop with a 27" monitor and an 11" MacBook Air, and team settings only override local settings when they're defined.