It is official - now Windows 10 is part of the recommended updates for Windows 7http://www.theverge....e-recommended-update
If you have the default Windows Update settings it will download and start the installation. Ok you can stop it but I can see my life getting busier over the next few weeks.
Not sure if this isn't actually criminal - I have some programmes that are not Windows 10 compatible that I rely on for work - an automated update would really mess with my business!!! Wait for the law suits
If you want to block Windows 10 upgrades altogether create these registry keys (you can create a .reg file in notepad and cut and paste the following - then double click the file and add the entries automatically):
Windows Registry Editor Version 5.00