You probably won't use it and shouldn't use it but when you say that someone will always find an exception to the rule (Viaweb, etc.). Basically there is no "super language" there are only working lines of code, usually in "Blub." Even Paul Graham says that the main (in fact only) benefit to a Lisp is one's ability to rapidly prototype.
Also "super languages" usually impinge rather than increase code readability, meaning that the one "genius" who wrote it has to maintain it forever since no one else can understand it, especially since he is likely to write it in his own modified dialect. This decreases the possible scope of any project, which means that even if new, innovative things can be done, they are not extensible and so remain at a relatively small scale (like Hacker News in Arc).
That's not to say that someone can't have a genius idea and implement it in a incomprehensible style that then can be re-written in Blub and extended so that lots of people can benefit from it. Actually, that's exactly what has happened in all of the Lisp success stories, not to mention every famous philosopher that's ever lived. But of course, if you are a "genius" you might also be able to prototype your product some other way.
As for FP on the JVM, there are limited but cool things possible. Although I would personally use it for prototyping only, it is possible you might have a use case (usually something to do with multi-threading) where it provides some improvement.
