More options is good! Centrally storing configuration is always a good idea.<p>Amazon OpsWorks manages configuration centrally via a web-based command and control.<p>Heroku manages configuration centrally via environment and heroku config:add.<p>ClusterFsck (did I type that right? :)) lets me store things on S3, centrally.
shameless plug, speaking of S3, I created a DSL for Amazon S3 (using s3cmd, because it is intended for my rake tasks) - <a href="http://jjuliano.github.io/s3cmd-dsl" rel="nofollow">http://jjuliano.github.io/s3cmd-dsl</a>