The second book in the Revelation Space series I found this to be a significant improvement and far more enthralling than the first, which was slow to develop.
Events from the first book are taken forward a level here. Some that were merely hinted at become central to this book, while there are traces of the effects of events in the first, throughout the second book.
The main storyline, of a machine intelligence bent on wiping out all starfaring sentient species continues, however unlike the previous book there is a more clearly defined story arc to Redemption Ark and a focus on developing the story to such an extent that you are completely enthralled in finding out more and more.
The characters in this book are also further developed than the first, and we are introduced to Clavain, an interesting character and one with many conflicts in his head.
The third book has already been ordered, about a hundred pages before I finished this one. This is a worthy read and I recommend the series to all science fiction fans.