Distress is a very unique novel. It is a quest for the intelect, a discussion of the implications of technology on our lives, and even more importantly, discussion about the implications of actual science on life.
If you want to know what the future will be like, Egan is a place to look for inspiration (although not for answers). Egan not only understands technology and science, and not only has the imagniation to forsee the future in ways which are original and thought provoking, but is able to see the social consequences of technology.
Egan's story, especially in the first two thirds of the novel, is an almost entirely successful and constant challange to the mind, in an enjoyable story. Egan's prose is powerful, and you can often enjoy his phrases, and while his minor characters are awfully indistinguishable, the two major ones, Violet Mosala and Andrew Worth, are very well realised and are sympathetic.
The novel contains ideas about the Theory of Everything. The theory of Everything is a unification of Einstein's theory of Relativity and Quantom Mechanics - it's a theory that can explain, at least theoretically, EVERYTHING, from the motions of planets to those of electrons.
The novel doesn't speculate as much about TOE itself, but about the social and psychological and even ethical responses of it, and it does so by introducing a pseudo-scientific religion which glorifies and demonises the descoverer of the theory.
This religion is interesting, but it is one of the two major failure of the novel because (slight spoiler here) it turns up that it is true in a sense. This changes the story from a scientific to a metaphysic one, and pushes us towards the realms of fantasy.
The other major weakness is that Egan's plotting and story elements are relatively poor. Crisises can be resolved in manners which are hardly satsifactory to the reader, in the sense that they rarely are well established or given proper pay off. Egan attempts to write a 'thriller' especially at the end, and it doesn't work.
But those are relatively minor problems. Distress is a novel of ideas, and thus it functions brilliantly. It'll make you think. So go read it.