Erlang is really good, especially for engineers with hardware background, who may find FP & Message Passing are more intuitive than OOP & Context Switching.
But it's quite difficult to hire.
But it's quite difficult to hire.
Huh? OOP & Message Passing!
http://lists.squeakfoundation.org/pipermail/squeak-dev/1998-...
(I'm in the SF area, but a lot of the ads I see are for New York and parts of the Midwest.)
* it has to fill a need people have.
* people have to know about it.
* it has to have a mature implementation.
Age helps with point #2 and #3.
With regard to JavaScript, the web browser pretty much forces you to use it. So it doesn't really matter how good or bad it is, it will have adoption.