Eiji Aonuma has confirmed that The Legend of Zelda: Breath of the Wild will have no Loading Screens in the Overworld!

[Shikamo]

It was expected but it is good to see that it is 100% confirmed :)

Gamekult: What motivated the choice of such an open, systemic world?

Eiji Aonuma: The wish to create an open world game came shortly after Skyward Sword was finished. We realized that the way you flew from one area to another, with no opportunity to walk instead, had frustrated a lot of people who wanted to know what was hidden between the regions. One of the greatest thrills of the Zelda series lies in exploring and looking for hidden things, so after a few preliminary tests, we reckoned that the Wii U had the power we needed to create a satisfying open world – one that would allow players to visit the entire world with no loading times. Everything stemmed from that intention.

Source: http://nintendoeverything.com/aonuma-on-zelda-breath-of-the-wild-full-gamekult-interview-translation/