This is nonsense for several reasons..
1. First, we have proof.. as in REAL LIFE EXPERIENCE that webkit browsers on mobile iOS/Android work MUCH better and developing for mobile web is far easier than for desktop due to almost no fragmentation. Yes, Apple introduced a couple of unique webkit prefixes on Safari for mobile but those are really not a big deal as you don't have to use them. They extend functionality and give some thing for iOS platform. You can still completely avoid using them and have the same code running on both Android and iOS.
So this whole "forking" notion is completely ridiculous. Everyone who joins Chromium/Webkit wouldn't really make it wildly incompatible because it's not in anyone's interest. That's why they switch to Webkit.
2. Webkit/Chromium support web standards better than any of the other browsers
So I don't know what the hell are people talking about "This site works with IE only" nonsense.
If everyone would join webkit there would be no need for that at all. We have THAT scenario now because of the incredible fragmentation among browsers.
Whatever your build for webkit based browsers on desktop works the same on all of them. It's beautiful.
You do understand that there is a HUGE difference between Microsoft and their proprietary browser they wanted to use to control the web and the open source browser that is one of the best web standards compliant browsers and is used by multiple companies making browsers.
In what world is this the same.
HTML5Test, seriously? You use that to prove a point? Let's not mention that a big part of the test doesn't test HTML5, and gives bonus-points for supporting stuff that isn't the standard at all! Also, supporting a feature doesn't mean it is according the standard.
Anyway, if you want fast innovation, than I gues you like Internet Explorer 6 very much. Because, back than, IE6 was the same as Webkit is right now. Yes, meet the new IE6: Webkit. It's naïve to think the web is better with 1 render engine, and you should know that, because we already have done this before with IE6. Fragmentation is stupid, everywhere, everywhere but browsers. It's important there are multiple render engines, it's important there are multiple browser. All with a significant part of market share. Webkit is now to big, look at mobile devices. Mobile websites doesn't work in Internet Explorer mobile or Firefox mobile, and that's a bad thing. It's not IE & FF problem, it's our, it's Webkit.
Webkit doesn't support the standard at all. It doesn't matter if it's open source or not, there are still people behind it that decide and they DO stuppid things. For example, gradients still don't work on Webkit as it is discriped in the standards. You need to use -webkit-, and that can't be how it should work. Webkit is taking over the internet, and that's not good at all!