The first third of this book is a five star white knuckle fall off the cliff ever accerating drop into the singularity. It's fascinating, breathtaking, horrifying, belivable and plausible. You're never quite sure what's coming, and you never catch your breath, but you're never completely lost either.

I distinctly remember thinking 'I have no idea how the heck he can keep this up for the whole book', and the answer unfortunately is that he doesn't.

Once you hit the second generation (loosely speaking) of characters, it seems to fall off the pace a bit, and slide from a harder grittier future to something a little more ephemeral and drifty. It's still good SF, just not as overwhelmingly awesome as it started out.

The last short section with the third (very loosly speaking) generation regains some of the spark, then the book ends quickly.

All in all very worth reading, and required for anyone who's ever been intrigued by the singularity concept.