Beware of spoilers as the latest Zelda game is out in the wild (at least digitally). While some may think this is due to copies getting sold early in Europe, the leak actually came from Nintendo’s servers.
Various tools online are capable of grabbing items from the official Nintendo servers including the ticket file which is used to fool Wii U’s into thinking you own the game. Even though the files were live for a fraction, users were able to not only pull the ticket files but the day one update as well (which is estimated to be around 2-3 GB).
Breath of The Wild is expected to launch this Friday for both Wii U and Switch, so until then it’s best to surf the web carefully to avoid spoilers.