It's my first Weir book and I've been told it's the best he's written so far. For me, I don't think this book lives up to its hype, but it's probably still worth reading for hard sci fi fans.
There are essentially two storylines in this book. The first one is a hard scify, high stake suite of scientific puzzles which makes most of the apeal of the book. This timeline is very well told, and its what keep me in the book. The use of scientific facts and phenomenon is clever and sometimes genius, quite understandable and believable. As am ecologist, I enjoyed how the book uses ecological and biological principles to make the plot go along.
The second timeline takes place in the past of the first timeline, offering insights into the present situation by the way of flashbacks. This second timeline attemps to be entertaining at the price of believability, amounting to some clunky world building. It is hard to explain without spoilers, but I found that story to use too many shortcuts just to make stuff happen and ignores some pretty important implications of what happens in the book (for example the treatment of climate change). In addition, I found most characters in this timeline to be one-dimensional clichés.
The main character, Ryland, is not even well fleshed out. We learn very little about him in the end, and most of his reactions to situations seems quite flat, lacking stake when we don't really know who is having them. The only motor of the book is Ryland's intelligence, which in the absence of a fleshed out character, just amounts to the author's showing off his intelligence.
The whole thing is not well written: I found the style too simple and repetitive. However it's very readable (it won't feel like you've just read 500 pages).
But in the end, did I enjoy the story? Yes. But it felt like every turn in the story was not really earned. Ive seen reviews saying it's a very "believable" sci Fi book. That's true for all the sci Fi parts, but only for those: characters are a bit caricatural and the social side of the plot lacks seriousness and insight.
Read this if you want a light and clever sci Fi read, but keep your expectations very low for characterization.
A good book for the series, mainly because it constitutes a turning point in the story. This sets the scene for what is the best book in the series (book 5).
A great book from the point of view of world building and the cool system of narration through foot notes. However some characters (for instance Nathaniel) are a little too flat to my taste.