Google's Chrome edged Mozilla's Firefox last month to take the number two spot in the browser popularity wars, according to an Irish metrics company.
Data from StatCounter, which tracks browser usage through the free analytics tools it offers websites, had Chrome with a 25.7% global share in November, a half-percentage point higher than Firefox's 25.2%.
In September, Computerworld used StatCounter's numbers to project that Chrome would pass Firefox no later than December 2011.
According to StatCounter, Chrome has gained 10.8 percentage points of usage share this year alone, vacuuming up nearly all the losses posted by Firefox (5.5 points) and Microsoft's Internet Explorer (6.3 points).
Internet Explorer (IE) accounted for 40.6% of all browsers used last month, StatCounter said.
Rival Web measurement firm Net Applications saw the Chrome vs. Firefox tussle differently. Its tracking put Chrome behind Firefox in November, controlling 18.2% of the market compared to Firefox's 22.1%.
But if both browsers keep to their recent trends in Net Applications' accounting, Chrome will pass Firefox in April or May 2012 to slip into second place behind IE. By that time, IE's share will have fallen to 47%-49%.
Both StatCounter and Net Applications noted an anomaly last month: IE either gained usage share or held stable.
Net Applications, for example, had IE holding steady at 52.6%, the same as in October, while StatCounter said IE had boosted its share by four-tenths of a point to 40.6%.
IE typically loses users each month in both company's eyes, some times in large amounts: In October, Net Applications said IE had posted a 1.8-point decline, while StatCounter had IE down 1.5 points that month.
Vince Vizzaccaro, vice president of marketing for Net Applications, did not have an explanation, only a suspicion, for the turn-around. "We believe there may be some anomalous data from last month," Vizzaccaro said in an email reply to questions.
If the data holds up, IE's turn-around from its precipitous decline in October will have been remarkable.
Microsoft did not address that today, but instead beat the IE9-on-Windows 7 drum one more time, citing Net Applications' claim that globally the browser is now more popular than either Chrome or Firefox on Windows 7.
IE9 on Windows 7 passed rivals in the U.S. months ago.
Among individual editions of IE and figuring in all operating systems, Net Applications still had IE9 in second place behind IE8, with the former posting a 10.3% worldwide share and the latter 28.2%.
But IE6 -- the browser Microsoft has been trying to kill for the last two years -- got a reprieve of sorts in November, boosting its share by half a point to 8%. Previously, IE6 had had a years-long string of losses.
StatCounter's take was at odds with its U.S. rival: The Irish company said IE6's share had dropped nearly three-tenths of a point to 2.2%, a decline in its usual ballpark over the last year.
Apple's Safari -- the clear-cut No. 4 browser -- remained flat (StatCounter) or lost share (Net Applications), during November. According to Net Applications, Safari fell four-tenths of a percentage point to end the month at 5%, essentially back at its September position.
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer , or subscribe to Gregg's RSS feed . His e-mail address is firstname.lastname@example.org .
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