Clearly, this issue is going to run and run, but i'd also wonder how many other operating systems are similar, and monitor users' activity.

I can understand about certain types of data being collected to improve the system, and previously, when the was a system crash there was a crash reporter. Other software does this on crashing, and users can choose to report it, and view what's being sent.

Speaking to PC World, Microsoft Corporate Vice President Joe Belfiore explained that Windows 10 is constantly tracking how it operates and how you are using it and sending that information back to Microsoft by default. More importantly he also confirmed that, despite offering some options to turn elements of tracking off, core data collection simply cannot be stopped:

“In the cases where we’ve not provided options, we feel that those things have to do with the health of the system,” he said. “In the case of knowing that our system that we’ve created is crashing, or is having serious performance problems, we view that as so helpful to the ecosystem and so not an issue of personal privacy, that today we collect that data so that we make that experience better for everyone.” Windows 10 Tracking Cannot be Turned Off [forbes.com]