Such a good book. Highly recommend to any scifi fan, but probably not going to be a page turner if you aren't into scifi already (e.g. you frequently feel scifi is just all endless world building).

Edit: It's funny reading others' reviews of this book... I'd never have bothered picking this up, because so many readers are calling out poor character writing. That's my biggest pet peeve with older SciFi. I don't know if I loved this book because the concept carried me through, or if I just disagree about the characters, but I'm very glad I've read this and I'm definitely reading the next book in the trilogy.