In Why Ruby is an acceptable LISP, Eric Kidd makes a good argument for Lisp geeks to consider Ruby.

I spent quite a bit of time recently with both Ruby (and Ruby on Rails) — and without a doubt, I consider it to be the most productive programming language (and web framework, respectively) that’s currently available. As usual, this might change once I’ve done a larger project with it — you just have to find out the hard way where exactly the tools suck (and all of them do, just to a varying degree). I used to hope for a good Lisp or Scheme+JVM combination, but I suppose Ruby will do just fine.