I should preface my comments with saying that my love for Alchemicals has been unreasonable for years. That out of the way:
Readers would do well to note that this book is a Manual of Exalted Power - not "Exalted: The Autochthonians." The detailed sections on the structure of Autochthonian society and chapter-long storytelling options for integrating them with Creation are gone. Instead we have a much more focused book that really delves into the nature, purpose and methods of the prototypes for all Exalted.
While I was disappointed at first to see some of my favorite 1E Charms not included, I'm glad they weren't because they've either been replaced by more broadly applicable ones (Transcendent Multimodal Artifact Matrix FTW!) or replaced with submodules. The writers did a fantastic job rewriting the Charm set in an intelligent, useful way that makes junior Alchemicals eminently playable.
That being said: some of the mechanical holes in the book (all those MA styles mentioned but not written! ditto Colossus and Municipal powers!), along with the lack of in-depth information about the cultures of the Eight Nations, beg for a Compass-style supplement for which I would pay hard-earned American dollars in a heartbeat.