Net Applications has also tracked the slow, steady decline of IE. Last month, said Net Applications, which monitors visitors to more than 40,000 sites, the majority of them U.S. URLs, Microsoft's browser share for the first time since the California company began monitoring browser market share.

According to XiTi, both Chrome and 's flagship Opera browser control larger shares in Europe than they do in the U.S. Chrome, for instance, ended November with a 1.1% share -- Net Applications pegged it at 0.8% -- while Opera owned a 5.1% share, more than seven times higher than the 0.7% measured by Net Applications.

Opera, which is headquartered in Norway, is Europe's only native browser maker. Since August, said XiTi, Opera has boosted its market share by 0.6 percentage point, all at the apparent expense of Firefox.

Traditionally, Europeans are much more likely than Americans to ditch IE and turn to an alternative. Earlier in the year, for example, XiTi said Firefox's market share in some countries, including Finland, Poland and Slovenia, was .