Staying power has less to do with relevance and more to do with legacy apps. There will always be some people working on any given technology. Be it Spring, Sma

Staying power has less to do with relevance and more to do with legacy apps. There will always be some people working on any given technology. Be it Spring, Smalltalk, Common Lisp or ...some X technology. The question is, is it relevant? In an increasingly Multicore world where you try to extract more performance out of your CPU's Ruby may not cut it and by induction Rails. The future web devs would require writing better multithreaded code probably on the JVM. Clojure, Erlang or Go are the few awesome options that come to my mind.