The fourth and final developer's preview of Internet Explorer 9 was released on Wednesday, with significant updates to standards compliance and rendering speed, according to Microsoft.
Microsoft said in a blog post that the developer's previews had been downloaded more than 2.5 million times, indicating that despite Internet Explorer's plummeting market share over the past few years, developer interest in seeing it improve remains high.
The vast and dramatic improvements made to Internet Explorer 9 are readily apparent, even in this stripped-down preview version. Hardware accelerated HTML5 support is a major and multifaceted component of IE9, allowing for more complex and high-powered audio and video support within the browser. There's also extensive SVG animation support, although, as Microsoft points out in its blog, the animated SVG standards have yet to be finalized. You can see how these differences affect real-world rendering when you run the IE9 preview's SVG tests in other browsers, since they render imperfectly. Still, Microsoft is forging ahead and appears eager to address standards compliance in IE9, which is a good sign.
The fourth IE9 preview also does better than any previous version of Internet Explorer on the Acid3 test, which compares a number of commonly used Web browsing technologies. The latest IE9 preview scores 95 out of 100, earlier versions of the IE9 preview scored 83, and the current Internet Explorer 8 only scores 20.
Correction 1:25 p.m. PDT August 9: This story initially misstated the Acid3 benchmark scores. The latest IE9 preview scores 95 out of 100, earlier versions of the IE9 preview scored 83, and the current Internet Explorer 8 only scores 20.