The Platform Preview is an early look at the Internet Explorer 9 platform so some features are incomplete, some may change, and some may be added. Microsoft asks that you refrain from providing feedback on features where noted that they are either partially implemented or not available. Microsoft is aware of their condition and will provide updates in future releases. Similarly, for known issues, Microsoft is also aware of their existence and are actively working on them.

Using and setting the home page. The default home page of the Platform Preview is the Internet Explorer 9 Test Drive site, which you can use to see demos for and information about the new Internet Explorer 9 platform. You can press F10 at any time to go to your home page. To change your homepage, right click the Internet Explorer Platform Preview icon in the Start menu and choose Properties. In the Target field on the Shortcut tab add your home page URL to the end of the path.

Developer Tools. The Platform Preview includes built-in Developer Tools. These tools help developers debug and understand the interaction between their sites and the browser. To open the Developer Tools, click the Debug menu and click Developer Tools, or press F12. The status bar indicates when the page generates script errors. You can use the Developer Tools to get more information about and debug script errors.

Create Shortcuts to Common Pages. To simplify navigating quickly to pages you commonly use you can create shortcuts. To do so, copy the Internet Explorer Platform Preview icon on your desktop and paste it to your desired location. Right click the newly created shortcut and click the Properties menu item. Update the Target field on the Shortcut tab to start the Platform Preview with the URL of your choice

Key features of Internet Explorer 9 Platform Preview:
Speed Demos: Take full advantage of your hardware with background compiled javascript
HTML5 Demos: Deliver rich interoperability with the next generation of Web standards
Graphics Demos: Create next-generation experiences with GPU-powered HTML5 graphics

Internet Explorer Platform Preview requires Windows 7 (x86 or x64) or Windows Vista SP2 (x86 or x64).
For Vista users, Windows Internet Explorer 8 and DirectX 2D (D2D) must be installed on your system. If youre not already running Internet Explorer 8, download and install it first. Then install DirectX 2D by installing the Platform Update for Windows Vista, available on Windows Update.