Got this notification when I opened Chrome when coming back to my desk after lunch.
"We changed our privacy settings to allow us to snoop on what you're looking at and shove you ads accordingly. Feel free to opt out, but we'll probably opt you back in when you aren't paying attention."
... the ad company IS Google
Firefox collects diagnostics and some usage data, not browsing history, Google collects absolutely anything and everything.
Their primary, nor secondary, source of revenue is not selling your data. You can also disable it entirely pretty easily. You cannot do that in Chrome.
Given the two options, one is clearly better.