Groovy, the Python of Java

Well said. I've been using Groovy heavily for the past year and a half or so, and have been thrilled with it so far. We're using Groovy on Grails for a significant portion of our startup project, and it has worked out very nicely. It's far more productive than plain-old-java, but it is (mostly) dead simple to learn and use for someone coming from Java.

Is Groovy better or worse than, say, Clojure, Jython, JRuby, Scala, PNuts, Fantom, Ceylon, Nice or Gosu? I don't know, but I know that - compared to Java - Groovy has been a big win for us.