(Find the report in : Visitors > Browser Capabilities > Browsers)
Two days ago, Google Analytics Blog admitted that the web analytics service intentionally concealed the identity of the new browser. "Because Google Chrome was not launched externally until today, we haven't yet changed Google Analytics to recognize it when you segment by browser within reports. However - this will change in the coming weeks (until then, the browser will show as Firefox)." The blog post has been edited and it no longer contains the reference to Firefox, but I can't help wondering if Google Analytics hides other things.
If you want to detect Google Chrome, this user-agent should be helpful:
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US) AppleWebKit/XX (KHTML, like Gecko) Chrome/YY Safari/XX
For now, most services don't detect Chrome, probably because Safari has a very similar user-agent:
Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US) AppleWebKit/XX (KHTML, like Gecko) Version/ZZ Safari/YY