David Herman has a lot to say about ECMAScript.next: his Mozilla blog is full of thoughtful updates, and he's been trickling steady updates of his talk on the future of JavaScript to various conferences for months now.

He seems pretty fair, too: in this recent post, for example, he praises a Dart cascade syntax proposal because it uses = for assignment -- because that syntax is quite intuitive, as well as familiar. The comments on that same post are pretty cool/subtle too (and don't all agree), and it's always fun to see new syntax under close scrutiny. David's blog is full of discussions at this level -- so if you're interested in syntax improvements, he's a great developer to follow.

For a briefer, less theoretical discussion of select ECMAScript.next improvements, try this post from Kishore. He loves JavaScript and Python both, and helpfully compares the proposed let keyword syntax, as in this example:

let even = [ x for (x in values([1,2,3,4,5,6])) if (x %2 === 0) ];

to Python's syntax (like CoffeeScript, perhaps).

If this sort of thing piques your interest, and especially if you love JavaScript but find it slightly annoying at times, it might be worth watching David's latest full-length presentation on the future of JavaScript (if you haven't already).