On most computers, Windows come preinstalled and is licensed to keep going until the end of the life of the machine. Alternatively, people will be able to buy retail licenses of the operating system which are lifetime of the user. This is not changed, at all, from Windows 7/8.
The only difference is that Windows 10 will be offered as an in-place upgrade for Windows 7/8 users for 1 year without additional cost. What isn't clear is if people whom upgraded are expected to pay something after that 1 year elapses. If there is a subscription service, that's where it stems from. Solution is simple: buy a user/machine license for the computer and you're out of that potential subscription service model.
Most likely, though, this isn't true at all. The free upgrade option likely is tied to the machine and that license goes to the end of the life of the machine. Microsoft's aim with this free offer is try to stop Windows 7 from becoming the new Windows XP and to ratify complaints and customer frustrations with Windows 8.1. They're hitting two birds with one stone which saves them money in the long run because they can kick Windows 7 to the curb as planned and they don't have to test and publish a Windows 8.2 update.
People who reinstall Windows frequently will not see much use in the free upgrade offer though. I suspect the free upgrade offer also doesn't work on systems that have been wiped clean (Windows 7 SP1/8.1 must exist already on the machine). This option is great for the rank and file computer users but probably not so much to the techie types. We're better off just buying the System Builder license like we usually do.
