The beauty of Clojure is that it let's you get as close to Java as you desire. Aside from installation considerations ("Do I have the right version of Java installed?") this is especially true in the upcoming 1.2 release. That is, with the addition of types and protocols it's never been easier to forget that you're on the JVM. I'm not sure what to make about your comment regarding XML, but if that is truly a determining factor then there are reasonable facsimiles of Clojure targeting .NET and Javascript (http://github.com/richhickey/clojure-clr and http://clojurescript.n01se.net/repl/ respectively).