I conclude that it's probably a good idea to keep configurations in the same programming language as the rest of the project. Of course, if you used lisp you w

I conclude that it's probably a good idea to keep configurations in the same programming language as the rest of the project. Of course, if you used lisp you wouldn't even notice :-) XML is ok if nobody (other than the original developer or the person who takes over later) has to look at them. Lots of OSX apps use XML in .plist files and nobody cares because that's just a detail of the class library the devs use and an OSX app without a nice configuration panel is unthinkable. However, visible XML configurations are a symptom that your app is about to be assimilated into the borg collective.