Gozo Shioda's book "Aikido Jinsei" has been published by Shindokan Books and is available now. The translator Chris Johnston is friend, a long time Yoshinkan student and teacher, and the publisher of Shioda's earlier book "Aikido Shugyo"
I understand that this book is not the same book that can be found on amazon under the name "Aikido: A Spiritual Journey" that is to be published later this year. "Aikido: A Spiritual Journey", is mostly a reprint of "Aikido Shugyo" and uses the translation by Chris Johnston. It is hard to tell since they are not using the same names for the books.
Sorry that this repeats information in other threads, but i thought i might tie the info into one post.