I'm a little late on this (this has already been discussed on the Keith Jarrett Yahoo! Music Group, as well as on KeithJarrett.it). Anyway, the musicians among you might be interested in "Keith Jarrett's Transformation of Standard Tunes: Theory, Analysis and Pedagogy", a book written by Dariusz Terefenko and published on March 11, 2009 by VDM Verlag. It's apparently very technical, so it's probably not for everybody.