Interesting and entertaining interview with Neal Ford of ThoughtWorks fame. He has lots of nice things to say about Groovy and Ruby.
The only point I disagree with is his assertion that in Groovy you can only do 80% of what you can do in Ruby in terms of DSL programming. I've never seen a Ruby DSL that couldn't be done in Groovy with a similar conciseness in the syntax. It would be nice if Neal could elaborate on this point.