WWE mentions the release this July of a new book that will detail all of Elvis' recording sessions from 1953 - 1977. This should include many new discoveries such as a lot more SUN session info; an unreleased 1956 home recording; '56-'57 "live" show recording info; much more info on movie recordings; close to complete TTWII and On Tour recordings; info on hundreds of soundboards; and more.
This seems to have been in the making for 10 years or more and is done like the Master And Sessions site where each take is listed and noted. This is not the JAT Recording Sessions book. Possibly it is hardbound and supposedly contains 666 pages. More information when we have it.