The big JVM language challenge

The Java Virtual Machine (JVM) is no longer the platform for a single language. While Java is a solid choice for just about anything, it has it's downsides too and the new guys in town are challenging it with shiny features:

• Scala, which combines object-oriented and functional programming

• Clojure, yet another dialect of Lisp, striving for multi-threading heaven

• JRuby and Jython, which bring proven and productive web development frameworks to the Java ecosystem, with all it's well maintained open source libraries.

• Groovy, which sits on the bottom of the popular Grails framework and was one of the first big steps towards productive web development on the JVM.

What we shall find out during this event is the advantages and disadvantages of those different languages and the practical implications of building applications in these.

Ideally, we would have a panel with 4 advocates of each language, as well as short practical demonstrations of each language - maybe even a coding dojo with one common challenge, which is tackled by everyone who brings a laptop simultaneously?

Any input on potential speakers and format is appreciated, will aim to hold the event in late January.