It's a preview version of Internet Explorer 10 (IE10), but to my eyes it's a complete web browser that is fine for anyone to install.
Unlike previous releases of IE10 for Windows 7, this is a complete interface, and it looks and works just like IE9.
My expectation is that Microsoft will only make subtle tweaks to this before releasing the final version soon. By "subtle", I mean there will probably only be little performance improvements, but nothing that most people would notice.
Because IE10 adds very good support for modern web standards, I can easily recommend it to any Windows 7 user.
Also, a VERY nice feature is that IE10 will automatically install updates to itself, like Google Chrome has done for a long time now.
Here's the download link. Click the Download button under "IE 10 on Windows 7 Preview".