Although Microsoft hasn't named a release date for IE9's beta, the six-to-eight week stretch between each Platform Preview may provide a clue: If the company sticks to the same gap between the fourth preview and the beta, the latter should show on or after Sept. 15.
"The IE9 platform is nearly complete," said Dean Hachamovitch, general manager of IE, in a detailed post on the browser's blog Wednesday.
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. That beta is slated to ship next month, according to comments made last week by Kevin Turner, Microsoft's chief operating officer.
On the Acid3 benchmark, which checks how closely a browser follows certain Web standards, the IE9 Platform Preview 4 scored 95 out of a possible 100, the highest ever for a Microsoft browser. The score was a 14 percent improvement over Platform Preview 3.
Hachamovitch hinted that the score of 95 would be IE9's best effort, arguing that the standards which prevent it from acing the benchmark are "in transition" and thus unlikely to get full support from Microsoft.
IE is on a two-month upswing in usage share, according to the most recent data from Net Applications, and Microsoft has to hope that when it ships in final form, that IE9 will be able to turn around the browser's long-term decline.
The 16MB Platform Preview 4 can be downloaded from Microsoft's site.
Unlike production versions, the IE9 preview can run alongside other editions, such as IE7 on Vista or IE8 on Windows 7. However, neither the Platform Preview nor the final version of IE9 will run on Windows XP, a sticking point with some users of that nine-year-old operating system.
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This story, "Microsoft sets stage for IE9 beta" was originally published by Computerworld.