This is actually very true. Having Chrome/V8 out there has definitely improved the state of browsers as far as performance; especially in regards to JavaScript. But now we face a situation where Google is getting such a market share with Chrome and their other web properties where lock in is a very real possibility, and the only way to keep an open, standardized web is to make sure there are still other browsers with…
Lock-in has already begun on Chrome. Now you can't install Chrome extensions from anywhere else but the Chrome store (which means only stuff Google agrees with). Chrome is as closed-down as iOS and WP8 right now (For shame, Google!). It's actually the main reasons I'm waiting to switch from it soon. But not until Firefox gets a security sandbox.
I get it, honestly. But hey, if you don't want lock in, the hell are you doing on Windows?