I suppose I should be happy that Iain M. Banks returned to the Culture universe after his disappointing departure in The Algebraist. There's nothing wrong with Matter, per se. So why was I so underwhelmed?
The draw of the Culture novels stems in part from their portrayal of a post-scarcity society and the subtle and dramatic differences this would breed in humanoid populations. To the extent that a Culture novel is set in a non-Culture society, some of the most fruitful sections come from an exploration of how the precepts of the Culture and the other community mesh. (The other main draw, at least for me, is the interactions between Culture Minds.) We get little of that here. Djan, the central character, lacks the psychological complexity of some of Banks's other protagonists and isn't forced into any significant conflict between Culture principles and her own desires. We see relatively few Minds, and, in what appears to be a concession to the idea that people just read about Minds for the funny names, their names are listed in an appendix. Does Banks expect us to skip the meat of the novel and just chuckle over them?
This book is something of a baffling mashup of other, better Culture novels. We have a generous dollop of Inversions (the struggle for power in a monarchical world) and some Use of Weapons flavor with the character of a Special Circumstances operative recruited from outside the Culture. A large part of the book plods through a fairly standard fantasy story set somewhere between sword & sorcery and steampunk. The characters in this plotline have a bit more depth, and Banks carefully changes points of view to highlight differences between self-image and reality, but this device is abandoned early on and we are then dragged along through a quest narrative that palls quickly. The impending danger becomes both obvious and uninteresting, and the necessary conditions for it are jammed in with little explanation (the Oct's actions, for example).
All this would have been fine, but after Banks turns out one of his standard Pyrrhic endings, he then appends an epilogue that is cribbed almost word for word from The Lord of the Rings. Anyone who reads Banks will know how completely disjointed and out-of-place this is. Is he tired of writing Culture novels and deliberately insulting the reader? Was this intended as some misguided attempt at fanservice? I cannot imagine any good reason why this was not scrapped. It leaves me with a poor impression of Banks, who seemed all along to be phoning it in. Recommended with reservations (check it out from a library).