This year the ES2015 / ES6 specification is a final draft stage and is only waiting for a final blessing. I’m even more convinced that the language is ready to use. In fact, why stop with ES 2015? ES7 already has some firm specs and the tools are even better.
Consider these points:
1. The technical committee responsible for ECMAScript specifications has committed to delivering a new version of the language every year.
2. The best way to keep up with the challenges presented by contemporary applications is to tackle those challenges using the best features of a language. ES6 is considerably better than ES5 and dramatically changes how to build and organize abstractions. ES7 should include better support for metaprogramming and async work.
3. Next generation frameworks, like Aurelia, are already taking advantage of ES7 features. It is natural for people who build frameworks like to stay on the cutting edge and use the best features a language has to offer.