IE 9 beta for Windows 7 and Windows Vista is out. This is the direct link for all the languages and 32 / 64 bit versions. Not all the languages have both the versions.
You can learn more about IE9 at Beauty of the Web where they have talked about features of IE 9 like HTML 5 Support, Windows 7 Integrated features like pinning, jumplist and aero support and hardware acceleration. Once you install the 19 Mb setup, it will download the required updates and will also reboot your computer.
Here are couple of snapshots and first look :
The interface is sleek and the first eye-catching difference is that the address bar and tabs are on same line compared to top and bottom in Firefox and Chrome.