While it's true to say "ECMA decided not to adopt", it omits the important information that most of the opposition came from Yahoo (AIUI Douglas Crockford was instrumental in this) and Microsoft, who might have their own motivations other than "preserving the feeling of coding javascript." And Google too, which is kind of a WTF given Dart.

I often wonder what the disadvantage is of moving to an existing, established, understood and already tooled language (such as the ActionScript family) if one is seeking to migrate away from a legacy language such as JavaScript.

Now I am using ActionScript to make a point, since I have not yet programmed in it to be able to address how much Dart does or does not mimic the AS syntax.

Is ActionScript "type-optional" as with Dart?

And I am so glad they did. I remember feeling unsettled by JS's lack of formal classes... and then I was enlightened.

I'm in the same boat. Back when I was a heavy AS3 developer, JS looked dumb and gimped. But once I drank the JS Kool-Aid, I saw the value in how JS does things. Not everything has to look and feel like Java. Now whenever I see frameworks that force classes onto JS, I have to roll my eyes.