This is a very fast moving novel indeed - in fact that is my only serious criticism - at times it almost feels rushed, and as a consequence some characters never fully develop, and certain plot elements jar. Also, some of the events and characters probably would make full sense only if you have already read MacLeod's earlier two novels, 'The Star Fraction' & 'The Stone Canal' (especially the latter). Certainly, there are subtleties that allude to both earlier novels that give a different take on the whole story.
That to one side, this is refreshingly clever, insightful, and witty SF. The technologies may have been seen before in other guises by numerous contemporary SF writers (nanotechnology, Artificial Intelligence gone rouge, difference engines, arcologes, etc., etc.). What MacLeod excels at however is an ability to create a credible, alien worldveiw. This story is essentially about a clash of anarchist world views, one socialist, but also deeply nihilistic and pessimistic about the human condition, the other highly capitalistic, individualistic, and almost naÔvely optimistic. Against this is the potential threat of possibly hostile, possibly benign Artificial Intelligences which may or may not represent the next step in human evolution.
It is a measure of his success that the human societies are credible, and their conflicts understandable. In Ellen May Ngwethu he also gives us a central character whose world view is very different to our own, and which is at times morally repugnant to our modern liberal western sensibilities. Her society the Solar Union in its egalitarianism and communitarianism may be superficially reminiscent of the Odonianism of Ursula le Guin's 'The Dispossessed', Iain M. Bank's 'Culture' or Peter F. Hamilton's Edinists, but its basis is very alien to the original blessing naiveté of most socialist utopias.
Above all else, the book has a sparkling, self referential wit. The chapter headings, for example are all titles of classic SF Utopian, Dystopian and disaster novels over the last century (even giving a sideways wink to his old pal Iain Banks in the process). Jokes at the expense of Arthur C Clarke are not too infrequent (never a bad thing in my book), and there is an almost camp sensibility to some of the action and dialogue (especially in the early chapters set on Earth).
A very clever book that keep you guessing to the end, throwing enough curve balls to keep you on your toes, and with enough action, adventure and character to make for a very enjoyable read. But do read his other novels first if you can!