Microsoft has started advertising Windows 10 to users of Windows 7 and 8 with the window that you see above. This notification window is now popping up for Windows users all around the world and it lets you register for a copy of the free new OS.
This notification should not be a surprise, the company made it clear that they would be pushing Windows 10 aggressively, especially since it is a free upgrade for anyone with a valid Windows 7 or 8 license (excluding corporations), and this is the first step of many to make consumers aware of the OS. While it is not exactly clear why only some users are seeing this dialog, Twitter is showing widespread reports of users having the prompt show up on their desktop.
Windows 10 is expected to be released this summer and we have already heard that the final signoff should occur sometime in mid July. Knowing that, it looks like the OS will be ready for the back to school season.
Microsoft is targeting 1 billion installs of the OS in the next 2-3 years which means that they will have to move aggressively if they want to achieve this public goal. Considering they are now directly advertising to their largest install base, and that the OS upgrade is free, they should have no trouble hitting this mark.