[pherq]

For reference, most of the surveys listed by Wikipedia[0] (not including that one, for some reason), list Firefox at about 30% in that period. I assume that the stats in your link comes from visitors to their own site, which given the focus (web development) seems like it could easily be biased towards more technical users (and thus over-represent Firefox compared to wider surveys).

[0] https://en.wikipedia.org/wiki/Usage_share_of_web_browsers

[pyrale]

Regardless of the peak value, your data tends to confirm that IE was on its decline before the introduction of chrome.

It is true, however, that chrome came at about the right time to capture a large share of its users (as well as a good share of FF users).