[Update: The book is also coming to Australia, UK, and other parts of Europe.]
Hyrule Historia is basically the Holy Bible of the Zelda universe. Not only is it jam-packed with concept art and never-before-heard secrets, it also resolves the grand Zelda timeline once and for all. Such a book is quite the collector's item, but as it was previously only available in Japan in limited quantities, most folks had no means to easily acquire it.
Dark Horse Comics has stepped up to the plate to localize Hyrule Historia for an American audience. If you've got $34.99 on hand, you'll be able to purchase the book when it arrives on January 29, 2013. Or you can go on Amazon and buy the non-English original for at least $65 more. I think the choice is obvious.
I'm so happy that Hyrule Historia is finally heading our way -- the demand for this massive tome has been immeasurable. The Zelda franchise is so rich in lore and developmental anecdotes that it would have been criminal had it stayed in Japan.