This novel is a vision of the Singularity -- that notion that if we track the progress of technology, we appear to be headed for a vertical asymptote sometime in the next century or so. It's jam-packed with brilliant and nutty ideas (and which are which is an exercise for the reader). I felt like the ball in a mental pinball game, which took some getting used to at first, but once I got into it, it was great fun, except when the horror of the future he paints takes over. The events in the story are so alien, the structure of the plot and the narrative so weird, that it's very hard to really identify with the characters; the examination of the human condition is, in a strangely effective way, more on the level of the whole species than on the few characters. But it works, at least to a degree, and it gives the reader a great deal to think about, as good SF should.
It's hard to say if it's supposed to be a cautionary tale or if I'm just hopelessly provincial in my pre-Singularity attitudes, but I find the general thrust of his future frighteningly believable. Start from a few assumptions about the nature of consciousness and what's technologically possible -- assumptions that one may not accept, but which we're working toward testing -- and the literally cosmic ramifications aren't merely within the range of suspension of disbelief, they're almost inevitable.
The main issue that determines whether this is a serious look at the fairly near future or a counter-reality thought experiment is whether it is possible to run a human mind on a computer if we just get enough information about the state of the brain and enough CPU cycles to run the simulation. For personal philosophical reasons, I don't believe this, so it's a fantasy story for me. But that's something I need to believe, not something I have real proof of -- if they actually succeed in doing it, it just means I face a personal existential crisis. Because if it really is possible for a person to exist in a computer, then it probably is inevitable that all of the mass of the solar system will end up in a Dyson sphere of computers.
**** PLOT SUMMARY -- MASSIVE SPOILERS ****
At the beginning of our story, in a comprehensible fairly near future, we meet our viewpoint character Manfred Macx. He's an eccentric genius who goes around inventing get-rich-quick schemes that really work -- novel new technological ideas with real currency -- and giving them away. His SO and dom Pamela is a control-freak who works as a tax collector for the decaying US government, trying to pursue people like Manfred who give away ideas that the US government wants to tax to try to pay the mountain of debt, and their relationship is on the rocks because he refuses to hold onto any of his ideas. Manfred is accosted by a strange virtual person who turns out to be an AI derived from the brain upload of a spiny lobster which escaped from its laboratory. Manfred arranges for the lobsters to enter into a contract to run a space probe -- implicitly recognizing them as people. SETI succeeds, and another copy of the lobster-AI gets beamed off as an answer. Pamela divorces Manfred, gets custody of their daughter, and is raising her in a terribly puritanical way. The daughter, Amber, manages to get a message to Manfred, who sends their robot cat Aineko, who by this time is clearly human-level intelligent, to the rescue armed with a bizarre legal instrument -- a trust which will revert to Amber on her majority, but which for the moment is an independent self-directed entity, to which Amber sells herself in slavery in a legally binding fashion based on the laws of Yemen where it is chartered.
Amber physically escapes to Jupiter orbit, where she manages to claim a moonlet as her own personal domain and start a process of self-replicating assemblers that turn the whole thing into smart matter. She's a little bit ahead of the curve, and ends up self-styled Queen of the Ring Imperium, very rich and politically important. Aineko casually reveals the fact that the second message from the ETs, which nobody human has been able to crack, is actually mental software which interfaces with the lobster upload which was beamed out. (Everybody else was trying to decode it mathematically as an independent message.) The source of the second message is a router on a superluminal galactic Internet around a brown dwarf 3 lightyears away, and Aineko has directions on how to talk to it. Amber directs the whole output of her kingdom to building a tiny starship consisting of a kilogram of supercomputer running its crew in simulation and a lightsail and then powering the lasers to drive it.
The ship arrives at the router and the crew goes through the wormhole network and arrives in the DMZ of a Dyson sphere civilization. Eventually they figure out that the builders of the civilization aren't there or aren't talking. The entities that are there are weird primitive parasites in the walls of the gods' house, despite being beyond human and dishonest, but they manage to escape back to their ship and even get a laser to send them back to Sol.
By the time they get back to Sol, things have gone rather pear-shaped. Amber's kingdom has collapsed and the original Amber killed herself, but not before she had a kid with Sadeq, the Muslim scholar Pamela tried to enlist to repossess Amber (Pamela converted to Islam, which by Islamic law made the minor Amber subject to Islamic law). A copy of Sadeq had gone to the router as ship's theologian, but that Sadeq was not at all interested in that Amber. Mercury has been converted into a shell of computronium around the sun, and most of the rest of the system out to Jupiter except for earth itself is in the process of being similarly disassembled. Sirhan, the kid, is a somewhat powerful person in the developing civilization being built on a terraformed Saturn (robot ships dive deep into the gas and harvest useful elements, which are built into giant balloon rafts which will eventually cover the whole surface). He eventually brings Pamela, Manfred's second wife Annette, and eventually Manfred himself (who had been experimenting with existence as a flock of passenger pigeons for a while, but nobody knew it was Manfred) to a weird family reunion which is interrupted when bailiffs from earth try to collect Amber's mind in payment for debts left behind by her other self. They scam the bailiffs by passing off an alien AI (described as something like the Economics 2.0 version of the cross between a pyramid scheme and a 419 scam) as a valuable ancient alien, and the original Pamela (who has stubbornly refused to upload or even to be rejuvenated, so she's very old) kills herself in the process of delivering the memetic bomb.
Then the rest of the family gets together and tries to figure out how to get humanity to agree to get away from the incomprehensible post-humans who are running the inner system. They lose the election, but the lobsters who have been aggressively colonizing the Oort cloud show up and rescue them. In exchange, some of the humans agree to explore the rest of the galaxy and report back to the lobsters what danger lurks out there. They manage to get away, and end up hijacking the router system, cannibalizing it for parts, and setting up a civilization in deep interstellar space which, while it has wealth far beyond the dreams of pre-Singularity humans (so much wealth that it can provide a comfortable existence for real meat humans without having to rely on being around a star -- not that Stross goes too deeply into explaining this), but is a terribly squalid third-world ghetto compared to the post-human intelligences. Still, they seem to have things pretty good, until Aineko (who had gone on the exploration mission and hadn't left a copy behind shows up. It seems that Aineko has received a message that purports to be from the Manfred who went, and claims to have found the answers to the big questions at the edge of the observable universe. But Aineko doesn't trust it, and needs a copy of Manfred to evaluate whether it's a real message or a trap. To accomplish this, he gets a ghost of Manfred reincarnated, reincarnates Pamela (he had enough information to recreate her, with his godlike ability to model human minds, even though she never uploaded), and reveals that most of the strife in the family's past -- particularly including the divorce -- was due to Aineko's manipulation. Manfred agrees to condemn a copy of himself to die to find out what Aineko needs to know, in return for the chance to live with the new Pamela and Aineko's promise to never trouble them again.
Definitely a must-read for folks seriously interested in the Singularity (even if you ignore the character interactions, the technological speculation is amazing). Extremely hard to put a rating on; this book will not appeal to everyone, both for style and for disturbing content. But I did enjoy it. 9 out of 10.