My first impression of Tarkin was that it is really short, with the page count of the actual novel at just over 260 pages. A book does not need to be long to be good, however, so while the page count was disappointing, it did not factor into the way I read the story.
The tale is essentially two different stories about the titular character that weave together to tell a broader story about who Wilhuff Tarkin is beneath his frown. The main story takes place around 5 years after Revenge of the Sith. It is a team-up story of Tarkin and the other character featured on the cover, Darth Vader. The two of them are brought together to find a small cell of rebellious revolutionaries (well before the formation of the Rebel Alliance that we all know and love from A New Hope and, more recently, Star Wars Rebels). Tarkin has had some experience with their methods from his days fighting in the Clone Wars. This is the first mission that he is working together with Vader on, so the reader can watch their camaraderie develop as the mission plays out.
The second story is a flashback to Tarkin's youth. He and his uncle, Jova, come from a wealthy and prominent family on a world far from the Galactic center. They are put together by Tarkin's parents because Jova lives in the wild and will train Tarkin to survive. This story is meant to show how Tarkin thinks and the reasons that his personality is as calculating and ruthless as it is in all the other media where he has appeared.
Quite honestly, I found the secondary story, that of Tarkin's upbringing, far more interesting than the primary tale. While it might be entertaining to many to see Tarkin and Vader getting in sync with one another and pursuing rebels without regard for anything in between them and their goal, for me it was a greater story to see where Tarkin came from and the planet which spit him into the undisputed third place in the Imperial hierarchy.
The Imperial characters in this book—mainly Tarkin and Vader but also the Emperor and some officials—feel in character and are fleshed out in interesting and mostly fulfilling ways. Tarkin comes across as a bit of a snob and comes to some correct conclusions too easily, but in some places his confidence in his intelligence and underestimation of his opponents hurts him as it does in A New Hope. The rebel characters in this book, however, are generally uninteresting and one-dimensional.
Overall, I would give this book a C+. I know of some online reviewers who really enjoyed and raved about Tarkin, but I cannot bring myself to fall into this category. The primary story was too dry, and, despite the shortness of the novel, dragged on too long for me. I understand that some important things happened throughout the course of the book, but I did not feel that the plot itself was important enough to the character or the galaxy to write or read about. The storytelling, as is Luceno's way, is great and probably of a higher class than most licensed novelists bring to the table. However, the first chapter of this wonderfully written prose is spent talking entirely about the design of a uniform. One of the things Luceno has excelled at in the past is pulling from all the other Star Wars material that exists, so I think he suffered here primarily from two things: a lack of ideas about what to do with the plot and where to bring the characters, and a lack of other resources to pull from since this is only the second canon novel in the Star Wars galaxy.
Now, a couple of notes for those who have read the book or do not care about spoilers.
1) So there's a lot of talk going around about how Palpatine's first name is Sheev, which is first introduced to us in this book. Do you like it or not like it? For me, I think this is mostly a moot point because it's not likely to start popping up everywhere. It's not the best name he could have been (I was kind of pulling for Frank, myself).
2) I can understand Tarkin's reasoning to come to the conclusion that Darth Vader was Anakin Skywalker, because he's working closely with him and has previously worked with Anakin. However, I believe it's a much bigger leap to see Tarkin determine that Palpatine is also a Sith Lord. And Tarkin doesn't care because he sees Jedi and Sith as basically the same, but Palpatine has unified a galaxy. Of course, Tarkin also knows that Palpatine started the war. I don't think that Tarkin just shrugging off this information is entirely rational, and I probably would not have had him reach the conclusion that Palpatine is a Sith Lord. Let him think Vader is the only Sith in the galaxy.
3) So Palpatine uses the Jedi Temple as the Imperial Palace. That's fine, I can understand that. But he does it because the Jedi Temple was built on a Sith lair? That's a little stranger and needs development in a future story. Does this mean that the Jedi have not been pure lightside since they built their Temple on Coruscant? Does this have no effect whatsoever, but maybe Palpatine wanted to recover Sith knowledge? Is this meant to be a social commentary exclusively, about how the Jedi and Sith go after the same things (like power and knowledge and exact locations for building)?
4) Just how important is Tarkin's ship? I don't think that Vader and Tarkin are going after these rebels because they stole the ship, because that is pure overkill for a ship that is basically falling apart by the end of the book. I think they are going after the rebels because these are the first rebels who are actually able to pull off something like this, and they must be shut down before they can organize into a larger force.
Of course, my opinion does not matter nearly as much as everyone else's. If you've read the book, want to comment on the points I've raised or should have raised, or if you'd like to discuss anything else about it, please leave a comment below.