If they haven't killed Windows 7 updates, this would not have happened. Nevertheless, this is quite an achievement and important stats for us as well. If Windows 10 is actually running on half of what they are saying, there is a good chance that we see everything focused on Windows 10. ie, game makers, software creators, theme makers etc.
ie, you make one single game and it will be ready to run on at least 50 crore devices. Imagine how much we can monetise if even 10 % of the total Windows customer use your game or software.