According to web metrics site StatCounter, at some point in December, Firefox became the most used browser in Europe with 38.11% versus 37.5% for Internet Explorer.
This doesn’t imply that Firefox is growing significantly in Europe. Instead, it shows how fast Internet Explorer has lost about 7 points to Chrome which grew by the same amount in the same period, plus two more points taken from Firefox.
Then there is also the seasonalization factor: people spend more time at home in the holidays, and browse less at work where IT policies tend to favor IE.
The win of course is for the web: with more browser diversity, the more it makes sense to code for web standards instead of for a specific web browser. One web, any device, any web browser.