Today, Microsoft is announcing the third Platform Preview (PP3) release of Internet Explorer 9, the company's next web browser version. IE 9 PP3 follows the previous release, PP2, by about seven weeks; PP1 was released during MIX'10 in March, at which time Microsoft said it would update the pre-release browser on a regular schedule. They've been far more regular than I anticipated, to be honest.

IE 9 PP3 continues the trends started with previous Platform Previews: It's a developer-oriented release, with no hints about a new UI or any other end-user features. This time, the focus is on GPU-backed HTML 5 canvas elements, so that all text and graphics are hardware accelerated, as well as HTML 5 audio and video. Microsoft tells me that today's browsers use less than 10 percent of the computation power available in a typical PC, whereas with IE 9, you'll get a better experience if you have better hardware.

IE 9 PP3 also supports ECMAScript 5, the latest version of JavaScript, as well as the Web Open Font standard.

In keeping with the creeping improvements we're seeing across the Platform Preview releases, PP3 includes further improvements to both performance and standards compliance. The browser's ACID 3 score is up from 68 to 83, for example. And its SunSpider score is very close to that of Safari 5, and above those for Chrome 4 and the shipping version of Firefox.

In addition to having now submitted a total of over 1600 compliance tests to the W3C, Microsoft has also released a number of new demos that show off features supported in this release. Here are a few shots of those demos and some related screens.

As always you can grab the new release (it should be up any time now) and find out more at the IE 9 Test Drive web site.

And no, there's no word yet on the schedule or when we can expect an end-user beta, or the final release.