I highly recommend people to switch to RubyNetBeans (the Netbeans support in Ruby) for people who prefer an IDE-heavy approach to development. I still use Textmate, but the integrated webserver support, shell script automation, and esp. the new debugger (which is still slow), is really useful.
RubyNetBeans
Hmm interesting, will do.
For fast debugging, be sure to follow the instructions at http://wiki.netbeans.org/wiki/view/RubyDebugging (which will require native Ruby as opposed to the bundled JRuby)