Chrome has 7% market share? I'm a Chrome user myself but that number is much higher than I expected. What's the source for growth? (those YouTube videos maybe?)
Doesn't surprise me at all, Google has the advantage that MS has - 'Brand Awareness' - Joe Q Public sees Firefox and sees a brand with no trust backing, unless they've already been preached to by a geek friend, but they see 'Google Chrome' and know that they trust Google/YouTube.
It doesn't really help firefox that many of us geeks are switching to Chrome|Chromium|Iron for various reasons, too.