This is not a new book -- it's copyright 1997 -- but I somehow missed it at the time, and I have to say that was a mistake. The more I read of Sawyer the more impressed I am, and that continues to be true even reading this older work.
The core story here is a modern day mystery; most of the actual science fiction comes in through the subplots and side stories. A whole bunch of stuff happens in this book, even though it's a short novel by today's standards, and most of it is interesting to think about. Sawyer doesn't get everything right -- there are a few points of the practical details of American society that he gets wrong, which I find slightly jarring, and there's some overarching philosophy that I don't necessarily agree with. But the science, the social speculation, and the philosophy are presented in ways that invite the reader (at least if the reader is me) to think about them, rather than beating the reader over the head with The Truth. I can't really say more without spoilers, which I wish to avoid more strongly than usual, because I'm actually hoping to encourage people to read this book.
This book isn't perfect; it has a fair number of flaws. But I find the flaws are minor and forgivable in a book that is worth reading for itself and that hopefully stimulates thinking about several matters that it's good for people to think about. This is a book I'd love to sit around and talk about with intelligent people. 9 out of 10.