Your point was, and I quote:
"Javascript itself was developed by a company (Netscape) in pretty much exactly the same way, for pretty much exactly the same reasons."
That's wrong on at least two counts:
1. ["same way"] Netscape had a monopoly, it wasn't injecting JS into a situation where there was already a scripting language widely used on the web and implemented among multiple competing browsers. It was not fragmenting a multi-lateral browser market or web content language ecosystem.
2. ["same reasons"] The Dart reasons adduced in the leaked memo are nothing like our reasons at Netscape for doing JS. We (marca and I, mostly) wanted a language for non-Java programmers, non-programmers even, which could be written directly in HTML. A language designers, beginners, amateurs could learn by the yard. We did that without failing to upgrade a prior such language already widely supported.
Dart, according to the leaked memo, aims to replace JS because JS can't be fixed. But who says JS can't be fixed? Why, the people making Dart, working at the dominant web company of the last decade! That's no "reason", it is a choice.
"I see the free market offering alternatives."
Uh huh. If Dart has native support only in Chrome, then it's not an alternative for people using other browsers. Then what?
The "free market" is a bogus political phrase. I'm in favor of markets: real ones that self-regulate by preventing fraud (a central clearing/blinding counter-party, bid/offer/open-interest/size transparency) and abuse of power (market winners capture governments -- this has happened throughout history, it's a big problem right now, see the Global Financial Crisis).
Talking about Google's anti-standards power games in the current multi-lateral browser market as if it's all "free market" goodness is b.s.
"If I'm not mistaken, IE supports Javascript, right?"
Think, floppybunny, think! IE supports JS because Netscape had a monopoly once it took over from Mosaic and grew the web via commercialization (SSL, another Netscape innovation). IE had no choice but to support "JScript", and indeed they were thus motivated to help standardize ES1. Standards, hmm.
Google has no such monopoly. The likely outcome of putting a native Dart VM into Chrome and (again per the leaked memo) using Dart for web app development in Google is not to make other browsers roll over and embed the native Dart VM as well.
Can you see Apple doing that? Microsoft? Mozilla would be expected to do it by all you bring-on-the-new-monopoly fanboys, but even if we did it wouldn't help.
We're in a multi-browser market. Competitors try (some harder than others, pace Alex Russell's latest blog post) to work together in standards bodies. This does not necessarily mean everything takes too long (Dart didn't take a month or a year -- it has been going longer than that, in secret).
Open standards development does not mean design-by-committee, either. Multi-browser collaboration among Apple, Mozilla, and Opera was what created HTML5.
Dart goes the wrong way and is likely to bounce off other browsers. It is therefore anti-open-web in my book. "The end justifies the means" slaves will say "but but but it'll eventually force things to get better". Maybe it will, but at high cost. More likely, it won't, and we'll have two problems (Dart and JS).
"Let's argue languages based on technical merits, not how or by whom they were developed."
Now that's just low. You know damn well that Google has kept Dart a secret, so none of us can assess its technical merit (maybe you work for Google and can?).
Sure, when Dart is released, let's argue in a new thread. This thread is about the fragmenting, essentially two-faced politics of the leaked JS strategy memo, and whether and why that's bad for the web.
If you want a new monopoly to sweep the web clean, bully for you. No such monopoly exists now, so realists will still have to work in standards bodies. Is Google really working in standards bodies? As Maciej Stachowiak points out in this thread and over on reddit, more and more of their extensions in Chrome are not being standardized, and apparently won't be proposed "later".