It's worth noting that Chrome was just legitimately a good product in a space where the competition wasn't blowing any minds. The people that switched over saw how much better a browser can be and spread the word.
Allowing the user to pull tabs into its own windows and merge them back was magic back then, as was including search and url in a minimalistic bar, when other browsers had 3-row bars at times. Such a simple and elegant product.
For a couple years Chrome was noticeably faster than IE/FF which is what caused tech oriented people to switch.
FF and even IE closed the gap for a little bit but once Chromes dominance took old I imagine the fact that no one tests things on FF any more has probably caused it to slip performance wise.
