Microsoft has made such leaks moot by offering Windows 8 itself.

On a new Windows Dev Center site, Microsoft provided links to three different versions of Windows 8.

The largest weighs in at 4.8GB and is a 64-bit edition that also includes developer tools such as a preview of Microsoft Visual Studio 11 Express and the SDK (software developers kit) for Metro-style applications.

Metro is Microsoft's name for the Windows 8 tile-based interface that borrows heavily from Windows Phone 7.

Two other editions, a 64-bit version (3.6GB) and a 32-bit version (2.8GB) of the operating system, can also be downloaded.