Mark Wilson writes: The various privacy concerns surrounding Windows 10 have received a lot of coverage in the media, but it seems that there are ever more secrets coming to light. The Threshold 2 Update did nothing to curtail privacy invasion, and the latest Windows 10 installation figures show that Microsoft is also monitoring how long people are using the operating system. This might seem like a slightly strange statistic for Microsoft to keep track of, but the company knows how long, collectively, Windows 10 has been running on computers around the world. To have reached this figure (11 billion hours in December, apparently) Microsoft must have been logging individuals' usage times. Intrigued, we contacted Microsoft to find out what on earth is going on.