Recent stories paint a confusing picture of Windows 10 forcing itself upon unsuspecting Windows 7 and Windows 8 users. Microsoft seems to have gone through more than it's fair share of buggy patches and updates recently, and it looks like this is largely responsible, rather than Microsoft megalomania.
Next year, Microsoft will move Windows 10 to the status of a "recommended" update, which will mean that most users with the default Windows update settings will be upgraded to Windows 10, unless they specifically deselect that option in Windows update.
It should be noted that Windows 10 can be "rolled back" to the original Windows 7 or 8 even after it has been installed, at least for about a month after the upgrade. Windows 7 and 8 themselves will continue to be supported by Microsoft as far as security updates until early 2020 and 2023 respectively.