Earlier today, it was revealed that Microsoft had bumped the NT Kernel version of Windows 10from 6.4 to 10.0. This change has been apparent since build 9884, which was compiled on November 9.
Earlier today confirmed that the news broke that this change was accurate, but if you were still in doubt, Microsoft has now somewhat confirmed this change in an MSDN document available to IE developers.
Developers preparing for Windows 10 should note that the Windows NT value in the UA string will change from 6.4 to 10.0 with the new release. If you have code that depends on the version number, we advise that you update to allow for the new value.
The MSDN document is asking IE developers to begin updating if they depend on the NT kernel version, because if not, certain websites and programs may have compatibility issues with the new Windows 10 operating system.
Read the full story here: Microsoft confirms Windows 10 kernel version bump to 10.0, asks developers to start updating