This is a fun, fast-paced space opera, the sort of story that would make a great movie. Zahn limits the information available to the reader in a way that creates some surprises as the story unfolds, but he does it in a way that makes the plot twists and shifting perceptions of who the good and bad guys are make sense, rather than just the author abusing his power so he can say "ha ha, fooled you again!" Railfans should also be pleased to know that he's created an interstellar railroad that actually makes sense. It all hangs together well, but I'm a bit disappointed, because Zahn stories usually have at least one really novel idea at their core. This book has some novel twists on ideas that other authors have explored before; from almost any other author it would be quite original enough to satisfy me. But the idea that's so unexpected that only Zahn could have written it is missing.
I am somewhat concerned that Tim told us at Chambanacon that this is supposed to be the start of a series, because he tied things up in this story pretty well, and doesn't seem to have left himself a whole lot of room to write more in this universe and keep it fresh. But with a whole galaxy to play in, there ought to be some surprises left.
Overall, a solid book and a fun read; good, but not, I think, outstanding. 8 out of 10. (It would be an awesome movie, though, so all you Hollywood moguls out there take note!)