Wouldn't having one implementation controlled by Google give them the final say in the standard though, and effectively all or most of the power over the standard? Seems like a dangerous road that we're heading down.
Google is already controlling the web now, with the existence of gecko. They control it because Blink/Chromium is much more popular than other choices, not because there is only one choice.
Keep in mind Blink engine is forked from WebKit (an Apple product) and Chromium is created from thin air. Yet it doesn't stop Google to have the dominant position they have today.
My point is, Google controlling everything is bad, but having only one engine (be it chromium or something else) isn't what causes it.
