This is an excellent reference work for anyone who has even a passing interest in Japanese cinema. Jacoby structures the book well, proceeding through all of the major Japanese directors (and many minor ones) in alphabetical order. For each director's entry, he provides a broad career overview - offering his own opinions of the major films - then includes a filmography. While I don't agree with absolutely all of his statements, his opinions are always interesting to read and well-informed, and it's nice to get a fresh (to me) perspective on such classic Japanese filmmakers as Kobayashi, Kurosawa, Ozu, Mizoguchi...
Another striking thing about this book is that Jacoby isn't snobby about which directors he includes. So he has "classical" directors like Mizoguchi in here, and also genre directors like Ishiro Honda of "Godzilla" fame and Takashi Miike. His willingness to cover drama, horror, science fiction, and gangster films in a single volume makes him more open-minded than most other aficionados of Japanese cinema, who tend to limit themselves to one or two genres. (Indeed, rare is the critic who enjoys both Tokyo Story and The Mysterians, as I do.) Another highlight is that Jacoby includes some useful appendices, such as an overview of the major Japanese film studios and a list of historical eras in Japan (handy for figuring out when all these samurai movies are supposed to take place).
Of course, since the book covers a lot of ground, Jacoby doesn't delve too deeply into any one director's work. Even "big guns" like Ozu and Kurosawa have short entries; and while Jacoby has room to challenge some common theories about Ozu, he doesn't have quite enough room to properly develop his counter-theories. Also, like most handbooks, this can get a little dry if you try to read it all in one go; I prefer to sample individual entries whenever I feel like it.
Overall, this is good stuff, and I look forward to using this book to track down the more obscure classics of Japanese cinema. As a pointless aside, many of the movies covered in this book have very amusing titles (in translation), on the order of: "Ninja Mountain Attack Saga: Duel by Autumn Moonlight!" Just thought I'd mention that, because it gave me a few chuckles.