Arthur C. Clarke was the man who popularised the term "the technology of an advanced culture will be indistinguishable from magic." The best science fantasy writers know this - George Lucas and Asimov make no attempt to explain lightsabres or positronic brains. And Clarke, of course, makes no attempt to explain the technology of an isolated Earth city 2 billion (or thereabouts) years into the future. Instead, the first half of this book gives us an entertaining and light voyage through a society stagnated by immortality and robot-assisted ease. When Alvin, the first child born in thousands of years, rebels against this society, we are taken along for the ride. He learns that his city of Diaspar is not the only community left on the planet, and he makes further discoveries that are fun to read about.
This part of the book is a reprint of Clarke's Against the Fall of Night, which was written early in his career and shows it. It is fast paced (perhaps to a fault), and we're surprised at the naivete of all the characters at one time or another. However, it's fun for a light read and recommended. The second half, written by Benford, is supposed to be a sequel, but bears absolutely no resemblance to Clarke's work. There are a number problems. Firstly, only 2 characters from Clarke's work survive, and they are relegated to supporting roles. Secondly, Benford makes the mistake of focussing on technology that is built 2 billion years in the future. This technology is used to fight the superbeing known as the Mad Mind, an energy-based species without physical form, but it's inherently silly to pit airplanes against a mental force. Finally, the "good" mentalic creature, Vanamonde, is ignored, even though its purpose from the first story is to fight the Mad Mind.
As a sequel, Benford's work is a disaster. Unfortunately, read on its own merits, it is no better. The main character is chased around and exposed to situations she doesn't understand, and she grows angry and frustrated at her experiences. We, as readers, share her anger and frustration. In the end, all that happens to her is a tour through the solar system. It's a whirlwind tour, however, so we are simply bombarded with images and it becomes boring.
I can generally rate books based on how long it takes to read them. The first half took a few days. The second half took a few weeks. Even television was more interesting!