Windows 10 - Unintentional Upgrades

In the last week or two I have gotten a significant number of calls from clients who have had PCs unintentionally upgraded to Windows 10.  While I generally like Windows 10, I do not believe that Microsoft should be doing what they are doing and essentially upgrading people automatically by using deceptive practices.  So far, I have not seen this happen on machines that were joined to a Windows Active Directory domain.  However, I have now seen it 10+ times on machines not joined to a domain.  Here is what I think you should know.
Microsoft is misbehaving:
If you receive the free Windows 10 upgrade notification and click the X, rather than simply closing the upgrade offer app, Microsoft considers this your acceptance of the upgrade and scheduled the upgrade.  This is absurd and inexcusable.  Here is an in depth story about this.
How to prevent an upgrade from happening if you wish to stay on Windows 7 / 8 / 8.1 etc:
Simply download and run the Never10 app.  A good description of how to do this can be found here:
How to roll your PC back to Windows 7 / 8 / 8.1 if you have been unintentionally upgraded to Windows 10 against your wishes.
Fortunately, this is very simple and so far seems very reliable.  Here are directions directly from Microsoft.
I hope this is helpful to you.