I'm not entirely sure I agree. The data also seems to indicate a significant chunk of users have moved from other dynamic languages. Perhaps they are the gateway drug?

I appreciate that clojure is less hardcore about its FP than Haskell, but it is still 'real' FP rather than the pseudo-fp of mutable-by-default, objects-first python, ruby, and javascript.

Anecdotally clojure delivers on some of the promises that those three languages (implicitly?) endorse (I've written python and javascript professionally for a number of years). I've dabbled in a bunch of FP languages (Clojure, Haskell, F#) as a result but I've settled in clojure. Haskell has many qualities that make me want to settle on it, but its strongest features (amazing static type system, full lazyness) is also the feature that causes me the most difficulty. In the end clojure provides more of what i was enjoying about python and js and much of what I like about Haskell but in a less frustrating way.

(caveat: I don't have a planet-brain - maybe if i did i would have settled on haskell instead).

When i answered the 'languages id go to question', i was assuming 'if clojure disappeared today', rather than 'which of these is clojure a stepping stone too'

The data is not clear about that. If I had taken this survey, my response to the following question would make you think that this was my first functional language, when in fact I have been exploring exotic languages for about five years.

"What language did you use just prior to adopting Clojure – or, if Clojure is not your primary language now, what is that primary language?"

Clojure is my favorite language right now and, if I had taken the survey, I would have answered "Java" because that is what I use for most of the day at my job. However, I have also used almost every language on that pie chart (except for Ada and C#) and would prefer almost any of those over Java (except for C, C++, and C#) if other people were not involved in the choice of my primary language.

Fortunately, I have successfully lobbied to have Clojure included in my workplace. I am very much enjoying the transition away from Java.

"Well, from this data it is the first functional language/drug for a significant proportion of users,"

Where in the data do you get that it is the first functional programming language for any users?

I haven't read the whole thing in detail, but in skimming through it a few times I didn't see anything that referred to any prior experience with FP.

Ah, point taken :)