I think the node.js people will be tossing out their old code and rewriting in a new language in a few years. When the number of cores on a CPU keep doubling every year or two, and you can use only one of them... you're not in a good situation.
I agree that duck typing is one thing that ECMAScript got right. However, Golang (Google Go) is able to do this without giving up static typing. I think that's the way to go... no pun intended. :)