Clojure's persistent data structures implementation is so good that I wish it were maintained as a separate library, which could be used independent of Clojure (for example, in Java or Groovy). I wonder if the existing implementation will survive the Clojure-in-Clojure transition.
JVM languages bootstrapped themselves from Java and for integration sooner-or-later you will run into situations where you must understand the underlying concepts. For example, writing web apps requires you to understand Servlets which is Java based. I come from Java background, have coded in Clojure and I speak from experience - you should learn Java if you are going to be on the JVM.
Oops! My fault. Since I am not a seasoned Lisp hacker (actually I am only a Clojure newbie), my subconscious filter didn't automatically detect it. I remember having read that distinction somewhere earlier. Thanks for the reminder. :-)
I am the writer of the article in question, and probably I can answer some of the points raised. (I noticed this entry late through the HackerNews RSS feed.)
@mahmud : I can understand your frustration. My target audience were Java people unaware of LISP/FP & benefits.
@jimbokun : I agree with what you said. The reason I said "lots of parentheses" is that's how most LISP newbies perceive it. I wanted to get people to agree with what I said before I can expect them to adopt. In a friendly way.
@yannis : I think even Rich Hickey's PDF was great. ;-)