A new leak of Windows Blue reveals that Microsoft considers Windows Blue as a relative minor update. A screenshot of the 'About Windows' screen posted on a Polish website shows that build 9375 has version number 8.1. Users of the Polish website leaked an earlier version (build 9346) of Windows Blue a while ago which makes it a reliable source.
There were many speculations that Windows Blue might become Windows 9 but it seems the update can be considered a feature pack and bug fix release to Windows 8. It's expected that it becomes available in August this year. The leaks of Windows Blue showed that the new features and improvements Microsoft is planning to make to Windows 8 are mainly in the Metro interface.
The changes that have been spotted until now are mainly new versions of default apps and additional settings that can be changed from Metro. So far Microsoft does not seem to plan to bring back the start menu or allow users to boot to the desktop.
