I don't believe it's primarily about advertising. Chrome startup on my Ubuntu and Windows boxes is an order of magnitude faster than Firefox, and significantly

I don't believe it's primarily about advertising. Chrome startup on my Ubuntu and Windows boxes is an order of magnitude faster than Firefox, and significantly faster than IE. I can open a Chrome window and navigate through two pages before FF even opens--even if I started FF first. That's a tremendous incentive to switch, even if Youtube videos are broken sometimes. :) I haven't looked back.