This is a fantastic novel from Alastair Reynolds who really took a gamble with this in my opinion, and it paid off spectacularly.
Throughout the book the author continually demonstrates his significant grasp of Physics (he was working at Cern at the time afterall), and his painting of a future universe which is not all wine and roses is refreshing.
However he does have a tendancy to let himself down by overdoing the physics by intoducing overcomplicated technobabble where its sometimes not required, this can detract from the tension that he has so expertly built up and this can spoil certain scenes.
The sense of claustrophobia and lonleliness with the Volyova story arc is masterful storytelling. The story builds to a tumultous conclusion which leaves you really wanting more from this universe and the characters involved.