Building a Clojure app with a command-line interface?

I just started w/ Clojure (coming from Ruby) and I would like to build an small app with a command-line interface. How do I handle input/output to a CL?

I noticed that there is a clojure.contrib.command-line, but documentation is slim.

http://github.com/richhickey/clojure-contrib/blob/ffa868411cda6c617105b52b4f6f9e0f37ee8c24/src/clojure/contrib/command_line.clj