The author is Junji Kobayashi of Tezuka Productions, who worked as an animator at Mushi Production and established Tezuka Productions' Animation Division. He worked on over a dozen animated works including the B&W version of Astroboy. He knows what he's talking about!
I'll say straight away that the book is fantastic. I have no interest or skill in drawing, but I appreciated this book purely on an Astroboy fan level. There is so much detailed information about Astroboy, not just on how to draw him but trivia and notes on his powers, mechanical design, etc.
The instructions on drawing Astro are very well laid out. The author goes into detail and differences on the original manga, the 80s series, and the recent 2003 series. One aspect which I think would be especially useful to aspiring manga artists is the way he does "this is wrong" and "this way is right" drawings side by side. The detail is so fine that at times I couldn't pick what was wrong, but once the mistake had been pointed out I realised Astro hadn't been drawn correctly.
He goes into detail on the history of Astroboy and the evolution of his design, including height ratio, hair shape, eye pupil detail, and even how many eyelashes he has. Speaking of which, in 1957 he had a rare nine eyelashes. Thought Jeffbert might be interested in that!
There is extensive information on how to draw his movement, poses, expressions, fighting, flying, digging, lifting, and pages of different clothes he has been seen wearing over the decades. There are also important notes on style exceptions in various poses and angles, as well as the differences between Astro and a real person.
This book is so comprehensive it's amazing - it even shows how to construct Astroboy using 3D modelling and what changes have to be made. There are detailed drawings showing how his leg jets work, two whole pages on his machine gun bottom (including the dimensions, calibre, and where the ammo is stored!

Overall, I rate this book very highly. I don't have a rating system, but if I did this would score 5 cool smilies out of 5. The beginning artist will find it easy to follow, with many drawings and sketches explaining how to contruct Astro using primitive circles and building up from there. The expert will also find it useful with all the handy tips and minutiae exclusive to drawing Astroboy that don't come up in other manga. And if you're not into drawing but just an Astroboy fan like me, you'll love all the great drawings, history and trivia.
B) B) B) B) B)