The first volume of Attack on Titan, shipping in Japan July 17th, will feature a 65 page protoype manga that author Hajime Isayama created at age 19. It also features sleeve case drawn by character designer/animator Kyoji Asano, illustrated card by Flowers of Evil's Shuzo Oshimi, and 12-page color booklet. A recent Tweet has offered an early look at the prototype's cover.
Speaking of previews, Hiroyuki Sawano's soundtrack is out June 28th (Sengoku Basara, Gundam Unicorn, Blue Exorcist)
For a bit more Titan fun, Shiori "Christa" Mikami parties like it's 845