Microsoft announced the availability of the IE10 Platform Preview for download today. The company calls it the “first step in delivering the next wave of progress in native HTML5 support.”

“We built IE9 from the ground up for HTML5 and for Windows to deliver the most native HTML5 experience and the best Web experience on Windows,” says IE Corporate VP Dean Hachamovitch. “IE10 continues on IE9’s path, directly using what Windows provides and avoiding abstractions, layers, and libraries that slow down your site and your experience.”

“We’re about three weeks into development of IE10, and based on the progress we’ve made, we want to start engaging the development community now,” he said. “At the MIX conference today, we showed the new browsing engine along with several new browser test drives that anyone on the Web can try out.”

The test drives can be viewed here. New HTML5 demos include: strict mode, tweet columns, Griddle, CSS3 Flexbox Flexin’ and The Grid System.

Internet Explorer 9’s adoption rate has been five times higher than that of IE8’s according to the Microsoft.

The browser is facing rampant competition these days. Firefox 4 is doing pretty well (currently with nearly 80 million downloads) and Chrome’s market share continues to grow. Mozilla and Google have both boosted their release process to launch more versions at a faster pace.

The IE10 Platform Preview can be downloaded here.