Making good on a promise two months ago, Microsoft today updated its Internet Explorer 9 (IE9) preview, a sneak peek that targets Web developers and others eager to try out the company's next browser.
"The Platform Preview continues to be the thinnest possible wrapper around the Web platform, and as such is not intended for general purpose browsing," cautioned Dean Hachamovich, the browser team's general manager, in an entry on the IE blog today.
In mid-March, Microsoft committed to updating the IE9 preview every eight weeks until it issues a public beta. The company again declined to reveal its timeline plans for a beta or a final of the next-generation browser.
Microsoft also updated the supporting IE9 Test Drive site with new samples to show what developers can do with its graphics processor-powered HTML, a key feature of the browser that boosts text and graphics rendering by offloading those chores to the PC's GPU (graphics processor unit).
IE9's preview will not run on the nearly-nine-year-old Windows XP, because the browser relies on APIs (application programming interfaces) built into Windows 7 and added to Vista and Server 2008 R2 in October 2009. The final version won't run in XP either, Microsoft has confirmed.
Hachamovich claimed that the second IE9 preview renders JavaScript about 20% faster than the March edition, and 36% faster than Mozilla's Firefox 3.6. Microsoft's early code, however, still lags behind the leaders -- Apple 's Safari, Google 's Chrome and Opera Software's Opera -- in SunSpider benchmark scores. Opera, for instance, was half again as fast as IE9's Platform Preview 2.
Microsoft's results nearly match those of recent Computerworld SunSpider tests, which showed that Chrome's newest beta was almost 20% faster than the current "stable" build, and that Opera continued to take honors as the fastest Windows browser.
The company also touted progress in the widely-used Acid3 benchmark, which checks how closely a browser follows certain standards, particularly specifications related to DOM (Document Object Model), CSS2 (Cascading Style Sheets 2) and SVG (Scalable Vector Graphics). Hachamovich said IE9 Platform Preview 2 scored 68 out of a possible 100 on Acid3, an improvement over the 55 scored by Platform Preview 1.
Unlike full-fledged editions of IE, the IE9 preview runs alongside existing versions of IE, such as IE7 on Vista or IE8 on Windows 7. Users can install the update overtop the March edition, Microsoft said.
Microsoft has said nothing about its goals for IE9's adoption, but the company has to be concerned with the gradual decline of Internet Explorer's usage share, which has been on a downward line for years and shows no sign of heading upward. The most recent data from Web analytics firm NetApplications puts IE's usage share at just under 60%, a record low.
IE8 has not been able to turn that around. Since IE8's March 2009 launch, Microsoft has lost 7.8 percentage points in usage share, only slightly less than the 9.2 points it lost in the 12 months preceding IE8's debut.
The second preview is a 15MB download, and can be obtained from Microsoft's site .
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 gkeizer@ix.netcom.com .
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