No more need to make a reservation. Windows 10 becomes an optional update, and in three months even a recommended update. But before it starts installing you have to confirm you want it.
Those on a metered connection should disable automatic updates if they don't want the download before saying no to the confirmation request. That's official now. After hiding this particular update they can go back to normal.
http://blogs.windows.com/windowsexperience/2015/10/29/making-it-easier-to-upgrade-to-windows-10/ tells more.