A damned fine book. In particular it seems to validate, complete, and compliment Kaleidescope Century, his most controversial book. To the newcomer - this is a very good book with which to be introduced to John Barnes. Barnes is all about extrapolating very interesting, and EXTREMELY detailed future histories. His characters' individual stories are interesting ways for him to bring his histories out.
This is the third novel in the history of the 21st Century that many people are calling the "Meme Wars" series by default. (Not really an accurate title, since The Meme War doesn't start until 2048, and the first book in the series, Orbital Resonance, takes places a whole 25 years before the Meme Wars and is concerned with a vastly different topic.)
There is also a short story, Delicate Stuff, in his anthology Apostrophes and Apocalypses. The author's blurb before this piece indicates that there will be a total of 4 novels in this series, but I suspect he could do MANY more.
This book does a reasonably good job of standing alone. You can jump into it without any previous exposure to John Barnes and follow along quite well. But what it does best is provide an alternate point of view to the extremely dystopian Kaleidescope Century. In KC, we see the 20th century unfold from the point of view of 2 psychotic mercenaries. Candle shows us some events that are very closely linked to events in KC, but from the viewpoint of two very decent people who were unfortunately born at a difficult time in history. The themes are the same - who's in charge? Who has the right to be in charge? And how does one balance personal needs and desires against the good of society as a whole? But the treatment is completely different.
On a grander scale, Candle illuminates (no pun intended) two very important background characters who have figured only peripherally in the earlier books - Phil and Monica. Phil and Monica wind up being among the greatest heroes of the early 21st century. Phil, under a previous name, developed the CSL curriculum which figures prominently in Candle and in Orbital Resonance. And later, Phil and Monica author the FreeCyber meme which represents earth's last stand against Resuna/One True.
(to correct a previous reviewer, Phil and Monica are NOT related to anyone in Orbital Resonance.... Although Josh Quare's adopted daughter Alice IS the mother of Randy Schwartz.)
My only beef with this book was the ending, which actually shocked me considerably. It wasn't a bad ending, but after reading Kaleidescope Century, I had a hard time believing that One True would suddenly go so "warm-fuzzy". (As a side note, I think KC would have made more sense if Candle had been published first.)
If you like this one, pick up Orbital Resonance for certain. I generally recommend Kaleidescope Century too... but be forewarned - that book is NOT for the squeamish. Although it does give a more thorough explanation of Disksters.