It's hard to top what others have said, since my thoughts are praised exactly. This book is indespensable for your journeys around Tokyo. It features larger maps for the more popular areas like Shinjuku, Tokyo, Akihabara, Ikebukuro, etc. and smaller maps for the surrounding "ku". I have looked around, and it seems this is the only book that is detailed, up to date, and best of all, *Bilingual*! This alone could be the most important key element while navigated through complicated Kanji names. I'll explain why this is neccesary.
I am in Tokyo now in a small area called "Kameari", where the large, detailed maps at the tarin and bus stops dont have the names in English. Although major stops and final destinations are in English, if you're travelling to anything other than the last stop, you're going to have a huge problem buying tickets unless you have a photograhpic memory or can actually read Kanji! This book is a godsend; not everyone understands English if you need help! If all else fails, just point!
My only minor gripe is that on only a few of the stations, it mentions certain exits (like South Exit and West Exit, but failing to mention "North Exit"), and certain department stores. There is an "Ito-Yokado" Department store in both Aoto, Kameari, and Ayase, but the map only lists the nearest Department Store as in Ayase! This is minor, but a little troubling at times, especially in the HUGE stations.
Finally, even the Japanese need to look at the map of where they want to go sometimes. Again I mention the "only in Kanji" maps at the Station. This book has detailed information on where the train and subway routes are. Using this book, I was able to find a solid route back to my apartment before the Station Attendants could! Coincidentally, I'm still finding new routes to take with different lines one actually saved me 160yen per trip! The Japanese have a very complex train system, but also very well done...if you know the ropes. This book is the threads that make up those ropes.