> The only reason for the difference in speeds between these languages is due to the quality of their interpreters, not the languages themselves.
That's not entirely true; there've been fairly good write-ups on particular elements of language semantics for which support inhibits VM performance; for instance, there were particularly good write-ups a while back by the JRuby team (Charles Nutter, specifically, IIRC) on Ruby semantics that are problematic in that respect.
Obviously, that doesn't mean that the level of investment by major firms in the interpreters doesn't have an impact, and Node is definitely riding high on Google's investment in making V8 speedy for Chrome. But language differences do matter.
That's not entirely true; there've been fairly good write-ups on particular elements of language semantics for which support inhibits VM performance; for instance, there were particularly good write-ups a while back by the JRuby team (Charles Nutter, specifically, IIRC) on Ruby semantics that are problematic in that respect.
Obviously, that doesn't mean that the level of investment by major firms in the interpreters doesn't have an impact, and Node is definitely riding high on Google's investment in making V8 speedy for Chrome. But language differences do matter.