Microsoft has pushed the giant button that
released Windows 10 to consumers around the world and on the company's campus, they have a large counter showing how many upgrades have been completed.
If you look at the video from the tweet below, you can see how quickly the figure is going up. While we don't know how many installs have been completed as the entire number is not shown, based on the short video, we can see that the figure is counting up at a rate of about 16 installs per second ( I was told that 16/s is a limitation on the counter and that the figure is actually higher).