After my less than wonderful experience with the Eclipse Ruby implementation (and don’t get me wrong, I LOVE Eclipse for Java development, and also learned a lot about how to configure it for other types of languages in this process), I did some research, and it appears that one of the most used IDE environments for RUby is TextMate. TextMate is not free, though there is a 30 day free trial period. It appears to be quite fully featured, and so I will be experimenting with it to see if it lives up to its promise.
Documentation is here.