Doing println() from future()

[Sdaas]

I am a noob to Clojure, and I am loving gorilla-repl ! I am trying to understand the expected behavior on calling println() from inside a call to future(). Something like ...

(future (Thread/sleep 4000)
         (println "hello world"))

Should I expect "hello world" to be printed on the screen 4 seconds later ? Right now, I can see that the future gets realized, but I never see the output.