As early news are coming, Windows 8 is available for download for OEM partners of Microsoft via Microsoft Connect.
The download is currently invite only, means if you got invitation then only you can download it, The full build number of this release is 7971.0.110324-1900, means it was compile on March 24.
As we are getting news from our sources you will be able to get your hands on beta version by the end of this year.
This release is labeled as “Windows 8 and Server vNext Pre-Release”.
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