One critic (an English Lit Ph.D.) hated the book because it read like a scientific paper, and, as-according to him-everybody knows, scientific papers are just dull enumerations of mundane facts. If that is your view of science and scientific papers, don't bother reading this book, you'll hate it.
If, on the other hand, you are actually fascinated by science, the scientific process, and the mysteries of nature, this book is for you. Many of Egan's books are about some kind of fundamentally new science, but this book is more of a kind of "speculative history of science": you get to follow an alien culture that, rapidly, goes through a flourishing of science and technology, following a path in some ways reminiscent of the human Enlightenment, and in some ways very different from it.
Some of the more subtle points about biology in the book are probably lost on many readers, such as the link between environmental catastrophes and evolutionary and cultural advances, as well as the different ways in which biological organisms are induced to procreate.
Beyond the scientific content, the alien culture of the book serves as a metaphor for the "nerd" subculture in our society: they have little interest in complicated interpersonal relationships and just enjoy simple companionship as part of their work, sex and procreation are fairly mechanical processes, differences in appearance hardly matter to them, and they are totally absorbed by their work.
But unlike the "Spocks" of so many science fiction series, this story doesn't bother contrasting the nerds with a "McCoy" that English lit majors or the rest of humanity can relate to. This is a story populated by "Spocks" talking, for a change, not in technobabble but real science.