Via the Microsoft Blog Post : Windows Keeps Getting Better.
Today at the JP Morgan Technology, Media & Telecom Conference in Boston, Tami Reller shared with the audience that the update previously referred to as “Windows Blue” will be called Windows 8.1 and will be a free update to Windows 8 for consumers through the Windows Store….
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We will also be making a public preview of Windows 8.1 available starting on June 26, timed with the Build developer conference in San Francisco. The preview will be available for Windows 8 and Windows RT.
