To be clear, I'm hoping for factual information to be presented about RxJS and how it relates to JavaScript's evolution, not a matter of opinion on how good RxJS is, etc.

My question is: is RxJS ( <https://github.com/Reactive-Extensions/RxJS> ) somewhat of a forward-looking polyfill because of [Object.observe](http://arv.github.io/ecmascript-object-observe/), etc. not being standard among browsers yet, or does it fundamentally offer things beyond the scope of what native JS offers *and* beyond what JS standards seek to offer in the foreseeable future? (Granted, perhaps someday native JS may be capable of X, Y, Z that aren't currently on the radar; I'm not interested in guesses on those.) Perhaps it's a combo.

My motivation/interest in the question is in considering the investment of learning and implementing RxJS in applications, weighed against the timeline of native JS solutions being available, and/or whether there are other considerations to be mentioned that I have not touched on here.