Instruct: Classify Amazon reviews into positive or negative sentiment
Query: That was an ending?

Endings usually entail finishing the plot. This book just wanders off at the end. No explanation for whatever happened to many of the main characters (e.g. Tom Orley), or what Herbie was really all about, just a lot of vague allusions to possibilities. As others have noted, the literary ploy where you: 1) end each chapter at a moment of crisis, 2) pick up the next chapter with other characters at some other place, and 3) then come back several chapters later to the first set of characters already past the crisis, is getting really old by this third book (or 6th, if you count the earlier books). The fact that Brin continues to do it over and over feels a little amateur-ish, like it's his only trick. It makes me crave some good Asimov or Herbert. It's unfortunate because Brin is generally a good and creative writer, with interesting ideas. But like many authors, the finished product on paper does not live up to the potential.