I wanted to inform that Windows 10 S is now available on MSDN to download.
Its a new build with security and simplicity in mind.
The biggest change in it is it’s a lightweight berion of Windows 10, booting faster and allowing it to be installed on small PC. The main drawback is it allow only app from windows store to be installed into it.
Windows 10 S is streamlined for security and performance, and works exclusively with apps from the Windows Store.