MiddleManagement works great for my needs, but if these libraries serve the same use case(s), I'd rather converge towards one library than have things spread out.

One other thing you may want to add is a retry loop for the heroku API calls. Every now and then, the heroku gem will throw a RestClient::ServiceUnavailable: 503 Service Unavailable exception. In the worst case, I'm not sure if this is best handled in the gem or at the application layer; however it's definitely worth retrying a couple times if you can avoid the blowup completely. I got some feedback from the Boston.rb group on handling this if you're interested: http://groups.google.com/group/boston-rubygroup/browse_threa...