<p>I've been reading about Ocaml's consistent speed, rapid prototyping ability, and excellent memory management, and decided to take it up.</p>

<p>As I've already got Ruby, *lisp, Haskell, and Erlang under my belt, I'm interested specifically in what KISS-violating features I should look out for in Ocaml.</p>

<p>If you've started Ocaml with a background in the above languages, what was the most frustrating thing to grok? How did you get around this difficulty? What analogies helped you get into the flow of the language?</p>

<p>I'd also be interested in knowing whether you have done more than simply learn Ocaml, and have actually converted to it for a large percentage of your coding problems.</p>

I found an excellent resource on Ocaml and its relation to most other languages:
http://www.soton.ac.uk/~fangohr/software/ocamltutorial/lecture1.html
Not only does it explain the why, it also explains many of the little quirks likely to snag you as you begin.
Ah, I found a
cheatsheet
highlighting almost all of its syntactic weirdnesses.