Players have been asking for this since the original announcement a few years ago. You wanted it, you got it, Killer Instinct is coming to the PC.
No release date or other info has been released except for the fact that it will be cross buy and will be cross play. Of course it will be coming to Windows 10. Remember, don't ignore that little icon on your taskbar, you can get Windows 10 for free if you are running anything over Windows 7.