Microsoft made a second Internet Explorer 10 platform preview available to developers on Wednesday. The software giant is improving its HTML5 support with Internet Explorer 10. “Developers will be able to build even more amazing sites and applications with IE10’s improved HTML5 support,” said Microsoft’s Dean Hachamovitch. “As different browsers support developers using the same markup to achieve the same results with great performance, we can all realize the promise of HTML5 applications.”

Microsoft has posted over 270 new tests to the Internet Explorer test center and submitted them to the standards bodies. Internet Explorer 10 platform preview 2 includes the following (full list here):

  • Positioned Floats
  • CSS3 Gradients (on all image types)
  • CSS stylesheet limit lifted
  • CSSOM Floating Point Value support
  • Improved hit testing APIs
  • Media Query Listeners
  • HTML5: Support for async attribute on script elements
  • HTML5 Drag and Drop
  • HTML5 File API
  • HTML5 Sandbox
  • HTML5 Web Workers
  • Web Performance APIs:
    • requestAnimationFrame
    • Page Visibility API
    • setImmediate

Internet Explorer 10, expected in beta form later this year, will only be available for Windows 7 and 8. Microsoft confirmed in April that it has no plans to offer IE10 to Vista or Windows XP users. Future platform previews of Internet Explorer 10 will be made available every 8-12 weeks. Internet Explorer 10 platform preview 2 is available for download at Microsoft’s IE test drive site.