I enjoyed The City of Last Chances, and this is a worthy successor. It's a sequel in only the loosest of senses: there's only a couple of characters from City of Last Chances that make an appearance. In another sense, it is continuing the same story: the story of the Palleseen's hegemonic expansionist forever war.
There was a section in the middle of the book where I wasn't sure whether it was as good as the first one: the story seemed to be dragging a bit, and the multiple perspective storytelling that worked so well in City of Last Chances just didn't seem to be working as well. But the book redeems itself in the last fifth or so. The disparate strands of the story come together perfectly and the final tense scenes are really good.
I titled this review "What if Pratchett but dark?" and I stand by that: …