To me it seems like it will be a modified version of the same map. If not, it would have been better off as DLC. However with this new threat, and the fact that it takes place some time after the first game, there is plenty of different ways Hyrule could grow.
If it took place in the same timeline and that is all, he would have stated as such. He specifically said, "the same Hyrule" which implies reusing the same map. For example, in Majora's Mask he specifically said Termina. In Phantom Hourglass the realm of the Ocean King was referenced specifically, and New Hyrule in Spirit tracks is on an entirely new continent. With that in mind, I feel he would have said a new region if something along those lines if it took place outside of Hyrule.
Who knows, maybe this will take Hyrule to the dark post-apocalyptic level many people originally thought the first game was going to be in at first...maybe darker...
Reusing the same map is not a bad thing if done correctly, and I have full faith in the Zelda team to do things right.
Don't worry, most have probably faith in them to pull it off again ;)
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