I agree wholeheartedly that functional languages allow the programmer to write code that is more succinct than imperative code. I personally love to use them because they allow me write code at a higher abstraction level than imperative languages. And any
Java programmer who is "scared" of closures is misguided. Closures add a tremendous amount of power to a language, and combined with Scala's type system, they allow one to express at the library level what in many languages can only be expressed at the language level.
That said the higher abstraction level comes at a price, and library designers have to walk a fine line to not only make libraries that are easy to use, but libraries that a programmer can grok just from the documentation. And I
hate reading through Scala source where the author doesn't explicitly declare a return type. That's just not being a good Scala citizen.
Overall I see Scala as a good language that I feel very productive in (although I fear feature-creep with each new version) that seems to be quietly gaining converts. I'll be interested to see where it goes.