Mozilla's Firefox Web browser has made impressive market share gains in Europe over the past few years. In the latest marketshare report released by StatCounter, Firefox 3 has finally surpassed Internet Explorer 7 as the most popular browser in Europe in a breakdown by version number.

Firefox 3 holds 35 percent and IE 7 has 34 percent in that region. The recent decline of IE 7 in the past week can largely be attributed to the release of IE 8, Microsoft's new browser. According to StatCounter, IE 8 has grown to 2.3 percent in Europe, with most of those users upgrading from IE 7. This change was enough to put Firefox 3 on top. IE 6, however, still has 11 percent marketshare, which means that all users of Microsoft's browser across all versions still outnumber the total number of Firefox users.

"The move is partly explained by a small switch from IE 7.0 usage to IE 8.0 but also by growing market share overall by Firefox 3.0," said StatCounter CEO Aodhan Cullen in a statement. "The data shows that Firefox is closing the gap and is now just 10 percent behind all IE versions in Europe."

When all versions are considered, IE has higher market share than Firefox

StatCounter's total scores for Europe put IE marketshare at 48 percent and Firefox at 38 percent. Opera is listed as the next most popular browser in the region with 7 percent. Safari and Chrome both rank lower than 3 percent, according to StatCounter. StatCounter's total worldwide numbers show IE at 62 percent and Firefox at 29 percent. Worldwide, Opera, Chrome, and Safari all have less than 3 percent. The numbers for North America are roughly similar to the global scores, but put Safari at 5 percent and Opera at less than 1 percent.

Firefox market share has already exceeded Internet Explorer in several European countries. For example, Poland has Firefox at 51 percent and IE at 36 percent, followed by Opera at 10 percent. Opera has a very large presence in several European countries, such as Russia where it ranks higher than IE at 37 percent.

StatCounter also supplies statistics about mobile browser popularity. Opera and the iPhone browser are tied this week at 22 percent. The next most popular is Nokia's browser at 18 percent and then the iPod touch at 15 percent and Android at roughly 2 percent.

The mobile numbers are very different for North America, where the iPhone and iPod touch dominate and Opera barely has any presence at all. The situation is reversed in Asia, where Opera dominates on mobile devices at 45 percent and the iPhone has only 5 percent. With the emergence of Mozilla's Fennec project, it's likely that Mozilla will make an appearance on these charts within the next few years.

Obviously, the manner in which these market share statistics are collected is not entirely scientific. According to StatCounter, their numbers are based on aggregate data from their own network of users, which includes 3 million websites and 4 billion page views per month.

The extremely high popularity of Firefox in Europe raises some questions about the validity of the European Commission's ongoing investigation of Microsoft's browser bundling tactics. Microsoft's browser is clearly not intractably entrenched in Europe, and Mozilla's success in the region demonstrates that third-party browsers can gain a strong position in the market.

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