Microsoft has decided to name Windows Blue as Windows 8.1. AngleWZR tweeted a link to a screen shot of Windows Blue build 9375, where in we can see that the operating system has been named as Windows 8.1. Microsoft adopted a similar structure for Windows Phone. Microsoft plans to refer to the Blue update for Windows RT (the OS specifically aimed at tablets) as "Windows RT 8.1," according to Mary Jo Foley's sources.
As for the release date, some other sources familiar with the matter said earlier this year that Microsoft plans to debut Windows Blue in August, while the first public beta could see daylight sometime in June.
Windows 8.1 (Blue) is said to be released in August, which the first public beta is rumored to be released in June. Windows Blue build 9364 was leaked on the web last week.