In a new upcoming Zelda publication (Hyrule Historia), Nintendo will be showing off a lot of artwork, much of which is beta concept designs from games such as Skyward Sword and Twilight Princess. Check out a few of the images below. This publication releases on the 21st in Japan, no known date for everywhere else yet. But here is a summary of what will be included in this book.
67 pages of Skyward Sword material and details, 70 pages containing the world of Hyrule and a timeline, artwork for several Zelda games, evolution of Link and much more!
Source: History of Hyrule