Without the watermark for the build number you can suspect that this will be what the next upgrades see as well as what gets downloaded by way of the MC tool. Why do you think that "Windows Feedback" option sits there nicely in the Windows Accessories for and 10 suddenly is a free upgrade? After 8 took a nose dive following how successful 7 was MS had to rethink how to get people to even move on anything new after that and getting everything smoothed out nicely before the full blown retail build does finally arrive and people have to pay for it!.
The transition should actually end up being more of a minor annoyance as far as taking 10+minutes to wait while you watch since it will go on like a service pack unlike what you generally see with a full upgrade of the OS. The impact on the registry shouldn't even be noticed while a program or two could stop functioning depending a few new entries or changes there while not expecting much. Your files, settings, and programs should remain intact.
PC build 10586 is now available to in the Slow ring!
So then is any word on a official ISO of the new build been released by MS