Microsoft has announced the availability of Windows 8 Consumer Preview aka the beta version of Windows 8.
The Windows 8 Consumer Preview is available worldwide for download in English, French, German, Japanese and simplified Chinese languages. More information about Windows 8 and how to download the Consumer Preview is available at http://preview.windows.com. The ISO files can be downloaded directly from here.
The system requirements/recommendations for the Consumer Preview include:
1 GHz or faster processor.
1 GB RAM (32-bit) or 2 GB RAM (64-bit).
16 GB available hard disk space (32-bit) or 20 GB (64-bit).
DirectX 9 graphics device with WDDM 1.0 or higher driver.
Metro style applications require a minimum of 1024×768 screen resolution, and 1366×768 for the snap feature.