Computerworld

Microsoft updates IE9 preview, beefs up HTML5 support

Third release of developer preview, but no word yet on public beta

Microsoft on Wednesday updated its rough-edged preview of Internet Explorer 9 (IE9), adding support for several crucial HTML5 standards and boasting that the browser is faster than ever.

Last updated seven weeks ago , the IE9 Platform Preview is not a full-fledged browser, but instead features a very bare bones interface wrapped around Microsoft's newest rendering and JavaScript engines.

When Microsoft debuted IE9 in mid-March, the company committed to updating the IE9 preview approximately every eight weeks until it issues a public beta. Microsoft has not disclosed a release date for either a public beta or the final version of IE9.

The third preview released Wednesday introduces support for HTML5's Canvas element -- the tag lets site designers insert dynamic, scriptable rendering of 2D shapes and bitmap images into pages -- as well as for hardware-accelerated audio and video tags.

Microsoft has pinned IE9's attempt to match or surpass the speeds of rivals on the browser's ability to offload text, image and video rendering chores to the computer's graphics processor, dramatically increasing performance.

"This is the first browser that uses hardware acceleration for everything on the Web page, on by default," said Dean Hachamovich, the browser's general manager, in an entry on the IE blog .

The company also touted the preview's improved JavaScript speed and Web standards test scores.

According to Microsoft , IE9 Platform Preview 3 completes the SunSpider JavaScript test suite almost 47% faster than its May predecessor, although it still lags behind production editions of Apple's Safari 5 and Google's Chrome 5 on Windows. Platform Preview 3 was more than 10 times faster at rendering JavaScript than 2009's IE8, Microsoft said.

On the Acid3 benchmark , which checks how closely a browser follows certain Web standards, the IE9 Platform Preview 3 scored 83 out of a possible 100, a 22% improvement over Platform Preview 2.

Unlike production editions of IE, the preview runs alongside existing versions, such as IE7 on Vista or IE8 on Windows 7 . Neither the Platform Preview or the final version of IE9 will run on 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, but not available on the nearly nine-year-old XP.

IE has been in decline for years. Although that slide has occasionally stalled, Microsoft has lost 8.3 percentage points in the last 12 months. The most recent data from Web analytics firm Net Applications puts IE's usage share at just under 59.8%, a record low.

Platform Preview 3 is a 16MB download, and can be obtained from Microsoft's site .