First of all, you did not cite market share numbers to show lack of an effective monopoly. You cited a fun wall chart of all the various browsers, most with tiny and non-growing if not rapidly shrinking market share back in 1995. Come on!
Edit: some stats from wikipedia:
Anyone around in the Netscape era knows that Netscape took over most of the market from Mosaic and smaller-share browsers, and evolved the web rapidly with proprietary (in the same sense I use against Google, however standardized later) extensions.
This led to Bill Gates' famous memo about the Internet Tidal Wave, and his cancellation of Microsoft's 1994-era AOL-killer, Project Blackbird.
Netscape dominated browser market share until IE came up to version 4, which was better on Windows than Netscape's old version 3 or very late version 4, and IE was bundled and locked-in hard to boot.
"It's hypocritical to blast Google ...."
Accusing me of hypocrisy shows ignorance of that word's definition in light of the history of my career.
I'm not practicing one thing and preaching another. I worked on JS standardization less than a year after shipping it in Netscape 2 beta. After that I co-founded mozilla.org. I'm not currently doing A and preaching not-A, nor have I been doing "proprietary" work for a long time. I've paid my dues.
Netscape was a monopoly in effect (it's very rare for a real-world monopoly to have 100% of the market). We did not have ability or time to make open standards of all our work. We knew, because Netscape had rejected a low-ball acquisition offer from Microsoft in late 1994, that Microsoft was coming after us. And we knew they had the power to kill us.
If we had not pushed hard to add programmability to the web (JS and Java in Netscape 2, plugins before in 1.1), then Microsoft would have been the reigning monopoly power, and would have abused that power (which did happen; it was prosecuted successfully).
So, though it's no justification in general, Netscape -- including my JS work -- did forestall a likely Microsoft push of their tech -- including VB as the Web scripting language. Monopoly good-cop/bad-cop act, or just history now, neither all "good" nor all "bad".
This is in contrast to today, where there is no browser monopoly and the top three have very close shares in many locales -- especially if you sort by model as well as make, and include WebKit variations on mobile, which is rising to eclipse desktop.
"Dart is going to be an open platform that is well-supported by Chrome and Android."
I think your sock-puppet is slipping. How do you know this? Do you work for Google?
Nice HN history you have, btw (two comments, both on this thread today). Why not do as on Google+ and use your real name? I have.
"First of all, you did not cite market share numbers to show lack of an effective monopoly..."
"Netscape was a monopoly in effect (it's very rare for a real-world monopoly to have 100% of the market)..."
I don't think you know what the word monopoly means. Market-share is entirely irrelevant. What constitutes the definition (the reason the term even exists: what is meant to describe) is not how "big" a company is, but the _exclusivity_ (as in: is anyone else allowed to ENTER that sector of the market). And using the words "effective monopoly" or "in practice/real world" doesn't work as a permission to misuse the term, either. In fact, it does the opposite. Actual real-world "effective" monopolies would be: An entity holding a patent for some invention, the State having exclusive control of force, etc, etc.
Some company being "the only company who is currently doing X" is not a monopoly, as long as anyone else can enter the market.
Dart is probably going to suck, though (and Java-stained ideas polluting its design will probably be the cause). Also, unless Chrome wants to commit suicide, it's gonna keep supporting JS in the current and future versions, so you JS people should put a halt to this soap opera. Pause thy bitchfest.
Whatever you call it, if Google had that now or very soon, it could indeed ship new stuff and "make it stick". Since it doesn't have that power, I repeat that Dart is fragmenting.
No one is obligated to work on extending existing standards only, not try injecting new ones. Doing both without market power to make the new ones stick is going to make a mess in my view. I keep saying this, do you disagree?
I'm the last person who wants to save JS from extinction. If it were cheap enough to kill, I'd do the deed myself. It's not cheap to kill -- quite the reverse -- and the leaked memo's assertions about it being unfixable are exaggerations at best, and betray a significant conflict within Google.
(BTW I agree there's a smell of "Java-stained ideas polluting [Dart's] design.")
If TC39 had a crack at standardizing Dart or putting ideas from it into ES6, everyone would be better off -- even if Google then launched Dart anyway.
Instead, while we in TC39 were working in the open on ES6 (which is past new-proposal freeze), we knew nothing. That is not just missed opportunity, I call it poor stewardship on Google's part.