I never thought I would like statically typed languages, but now I don't know how I can live without them.

Scala is also more functional than Ruby or Python. I use it in a hybrid OO/Functional style. I probably lean 80-90% functional though.

As for people complaining it being hard to read, I disagree. Sure, some people try to be clever and play the, "how much can I reduce this code down to as few lines as possible" game. But if you break things out and not chain too many combinators or use too many symbolic operators, it can be readable. I don't find it any more difficult or easy compared to any other languages out there. It's just how you write it.

I think the biggest hurdle is to find a good mentor to give you the ah ha! moment when learning Scala (or any other functional language). I don't think many people can learn it by themselves. But once someone shows you how you can write your app in a more functional way, you begin too see some of the benefits of FP.

In terms of elegance and succinctness, Scala is somewhere in the middle between Java's bureaucratic verbosity and Python's terseness.

Ruby forces new lines for many expressions that Scala doesn't. (Think class with accessors vs a typical case class.) as things get more advanced, Scala allows you to express things that can be very difficult or awkward in Ruby. Like function composition, currying, pattern matching.

There's not really a case where a Ruby program will typically be shorter than a Scala program (well, excluding imports since there's no shared global namespace in Scala), even if you're avoiding typelevel style programming.

"Java Python programs are generally expected to run slower than Java programs, but they also take much less time to develop. Python programs are typically 3-5 times shorter than equivalent Java programs."

I think Python performance wise a less attractive options than Java or Scala. At least according to the authors. Development time is a different question.