You can't get an interoperable spec of a new edition of a language the size of JS in less than three years, for any such language. Not for Dart (which is still changing and by Google's own plans nowhere near ready to standardize) or TypeScript (also new, and tracking ES6). Java, C#, Python, Ruby, etc. were built to today's state over years or decades.
Bite-sized specs are much better. Small libraries on github and universal edge-caching, even better. Could we have bite-sized specs for JS?
As I speculated at Strange Loop last week, with a few final gaps in the language filled (Object.observe, slated for ES7, weak refs and event loops, and definitely macros! see http://sweetjs.org/) by a future JS standard, we will be "all but done".
Working away at this goal,