I'm interested in learning ruby. But the most important thing for me is, if there are any good editors for that. That will help me decide if it's worth to switch from PHP to Ruby.
I, and many other people, use and prefer TextMate for Ruby on Rails work. Many Rails developers use Macs and TextMate is the go-to editor on Macs.
And yes, it is worth it to switch from PHP to Ruby.
See this question: http://stackoverflow.com/questions/59968/best-editor-for-ruby.
I prefer to use the Netbeans IDE with jvi a vi emulation plugin.
on windows, i have been using InType. its in alpha right now, but it works pretty well for me.
otherwise, TextMate is the way to go for Mac OS X.
for linux my roommate uses gedit, he loves it.
for the record, its not the text editor that will make you wanna switch.
Try Komodo Edit if you're using Windows or Linux. There's an introductory screencast at http://www.rubyhead.com/2009/04/24/komodo-edit-textmate-alternative