Dear Fedoreans,
Having followed the debate over whether to flag init scripts as %config files, I thought that there's a feature of another package manager that I liked: when a config file has changed, it asks you if you want to keep your local copy or if you want to install the package's version. RPM is non-interactive, so it's not supposed to do this. But I thought this could be implemented in a yum plugin.
I've written a plugin which does just this: http://gauret.free.fr/fichiers/rpms/fedora/yum-merge-conf/merge-conf.py http://gauret.free.fr/fichiers/rpms/fedora/yum-merge-conf/yum-merge-conf-1.0...
Add the --merge-conf command line option to your yum update, and it will ask you what to do with those .rpm{save,new} files as the packages are installed. You'll be able to diff the files, choose your version, or spawn a shell to check further.
If you think you could be interested in this feature, please have a look. If you think it's a useful plugin and it's decently written (it's my first yum plugin), I'll submit it to the yum list.
Cheers,
Aurélien