Mitchell's Boy Toy writes "Firefox's market share has hit 28.0% in Europe as of December 2007, according to a French web metrics firm. That's a 20.7% increase from the beginning of 2007. 'Finland currently has the highest Firefox market share in Europe with 45.4 percent, followed by Slovenia with 44.6 percent and Poland with 42.4 percent.' IE share fell to just 66.1% in December, a 0.9 point loss in just a month. It should also be noted that Firefox's success could spell trouble for Opera's antitrust complaint: 'Firefox's continued success in Europe may undermine some of the arguments made by Norwegian browser maker Opera in an antitrust complaint filed against Microsoft in December of last year. Opera accused Microsoft of abusing its dominant position in the web browser market by tying Internet Explorer to Windows.'"