I feel like any review I make of this novel will be an unfair one, so I heartily recommend that you read some of the absolutely gorgeous reviews already out there, but I will leave you with a single impression: 
 The Uncertainty principle Thus applied to writing fiction (or Science Fiction): You can know where a story is at any point in time or you can know its velocity (it's pacing), but you can never know both at the same time. 
 :) 
 Seriously, this book is pretty damn awesome. Each of the nine viewpoints are grounded so deeply and across wide spaces and cultures across the Orient, and truly fascinating in their own rights, that it'd be easy to read the whole novel from a light-theme touch a-la Cloud Atlas, but instead, we've got a seriously strong SF theme going on here. 
 It's been out long enough that I'm not going to worry about broad spoilers, and knowing a few facts might actually encourage new readers of Mitchell, especially if you're into SF. 
 Quantum intelligences, people. Yup. Disincorporated personas. Ghosts. And a bit of a fourth-wall breaking if you read REALLY carefully or just make an interpretation from the damn title of the book. :) 
 Someone's been doing a bit of backpacking across PoVs, and I think this book might be seriously more fun to read the second time around, knowing what I now know. 
 Can I trace some newer novels like Touch and The Lives of Tao back to this book? Well, I can try. :) Do I think it might be a great companion piece, just in sheer scope, to The Boat of a Million Years? Yes I do. 
 Do I think this novel might have made it REALLY huge in the eighties? Um, yes! Do I think it's also way before its time? Sadly, yes, that too. But it doesn't change the fact that it's pretty damn virtuoso and possibly a bit more interesting in some ways than Cloud Atlas. I know people like to go on about how the other novel is all that, but there was something about this one that knocked my socks off a bit more. :) 
 All I can say is, have fun tracing all the threads! I can almost guarantee that you'll never trace them all without an atlas. There are a ton of easter eggs just popping up between the different stories here, a representation made small when you think about what Mitchell has been doing with the rest of his novels together. 
 I'm not surprised, of course. This is a first novel and all first novels like to set up a promise to the readers that will be continuing on a later journey with the author. :) 
 I'm pleased! I will be continuing this ride, later, and perhaps I'll go backpacking! :)