Google's Chrome 15 has jumped into the number one spot, replacing Microsoft's Internet Explorer 8 (IE8) as the world's most popular browser edition.
Ireland-based StatCounter announced the passing of the baton today, citing data from the last three weeks that put Chrome 15 ahead of IE8 starting the week of Nov. 21.
It was the first time that IE8 had not held the top spot since early 2010, when it replaced IE7 as the most-widely-used browser, and the first time a non-Microsoft application has led the list in StatCounter's tracking.
During the last two weeks of November and the first week of December, Chrome 15 accounted for 24% of the global browser usage market, compared to IE8's 22.9%. Mozilla's Firefox 8, meanwhile, held a 14% share during that period to take third place, and IE9, Microsoft's newest version, had the fourth position with 10.4%.
Overall, IE retained its aggregate lead over Chrome, with Microsoft owning 39.5% of the market those three weeks compared to Google's 26.5% and Mozilla's 25.3%.
In the U.S., IE8 retained its top ranking, with 27% for the week of Dec. 5, nearly nine points higher than Chrome 15's 18.1%, StatCounter said.
But Chrome 15's global fame will be fleeting. Google released Chrome 16 on Tuesday , and with the browser's automatic upgrade mechanism, most users of 15 will soon be running version 16.
Google's latest coup was the second this month: According to StatCounter, Chrome pushed past Firefox in November to snatch the second cumulative spot behind IE.
U.S.-based Web measurement company Net Applications -- which does not publicly release weekly stats -- had a slightly different take on Chrome 15's market share.
Net Applications' data showed Chrome 15 with 14.6% of the worldwide market last month, in second place, but with only about half IE8's 28.2% share. Behind Chrome 15, said Net Applications, were IE9 (10.3%), IE6, of all things (8%) and Firefox 8 (7.3%).
Those IE numbers will change if Microsoft new IE upgrading practices take hold. Today the company said it will automatically upgrade IE6 and IE7 on Windows XP to IE8, and upgrade IE7 and IE8 on Windows Vista and Windows 7 to IE9.
The new scheme kicks off next month in Australia and Brazil, and will be expanded to other markets, including the U.S., over time, Microsoft said.
Microsoft characterized the change as a way to push users to more modern browser, a move that will make "the Web overall better -- and safer."
If users don't opt out of the auto-upgrades, IE6 and IE7 shares will decline, something Microsoft has been aggressively promoting for IE6 since mid-2009, and amped up last March with the debut of a special IE6 "deathwatch" website .
Chrome 15 edged past IE8 late last month to take the top spot among browser editions. (Data: StatCounter.)
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer , on Google+ or subscribe to Gregg's RSS feed . His e-mail address is email@example.com .
Read more about browsers in Computerworld's Browsers Topic Center.
Join the CIO Australia group on LinkedIn. The group is open to CIOs, IT Directors, COOs, CTOs and senior IT managers.