If readability were the only factor I considered in rating this book, I'd have given it only two stars. Frequent naps were needed to get through the book because it kept making me drowsy. But the author did try to imagine the unimaginable - that is, to conjure up a picture of the post-singularity future. So I'll give him credit for taking a stab at the impossible. That vision, unfortunately, lacks even the tiniest smidgen of credibility. It's just out-of-control imagination, and it's very tedious to read.

Iron Sunrise was by far the best book of the series. Its plot line and characters were intriguing, and it hinted that some race (the Remastered or perhaps their "gods") was able to hide events from the Eschaton and maybe even threaten or destroy them. This turned out to be a major, dangling plot thread that was never addressed in Accelerando. The lack of follow-up was very disappointing.

So Accelerando is the back-story for books 1 and 2. Pre and post singularity events play out, starting on Earth and spreading out vastly, that presumably lead to the rise of the Eschaton. But that eventuality is only very loosely implied by the ending, and the Eschaton is never actually encountered in book 3.