The crux of the problem is that Gross can't take us on a tour of the picoworld, the femtoworld or the attoworld where the real mechanics of the nanoworld must lie hidden. Depending on the reader's background this book could range from being a big bore to being quite interesting. Most of his speculation about nanotechnology is borrowed from Drexler. If you've read Drexler there is no point in rereading it here. However briefly, he does warn that this fiddling in the nanoworld could result in ultimate bacterial weapons and freaky humans. Boiling down the message-much of Gross' nanoworld tour consists of illustrating activity within cells and bacteria. He is like a man looking at a bird in flight and saying, "Look, man can fly too." When he goes off on tangents like the blue rose, the green genes and pressure squeezed eggs the reader realizes he is grasping at straws.
Much of the book explains how x-ray crystallography, NMR spectroscopy, and laser pulse photography are used to magnify and stop the action occurring within the animal cell. In this way he reduces life, the cellular processes, to those like message transmission, transport, protein folding, and protein synthesis /catalysis. He speaks of the new fields of biotechnology and genetic engineering to change the DNA blueprint but that is what evolution has been doing for billions of years. What's new here beyond splicing into the bacteria's DNA to create drugs like insulin or frost proof vegetables?