http://www.microsoft.com/windows/products/winfamily/ie/ie8/default.mspx
Internet Explorer 8 Beta 1 (Developer Preview)
Welcome to the website for Internet Explorer 8 Beta 1. Internet Explorer 8 Beta 1 is a developer preview for web designers and developers to help prepare their websites for the launch of Internet Explorer 8. Some of the new features designed for developers include a developer toolbar and improved interoperability and compatibility.
Internet Explorer 8 is designed to work in standard mode out of this box. However, Microsoft provides a way for users to browse the web in a way similar to Internet Explorer 7 by using the emulate Internet Explorer 7 button on the chrome. Learn more.
The web at your service
Internet Explorer 8 will take the web experience beyond the page. Internet Explorer 8 introduces a new way to seamlessly experience the best of the web whether you are a web developer writing to standards or a user discovering a new online service. Be one of the first developers to take advantage of improvements in Internet Explorer 8 for your websites and applications. Learn more.