Star Trek: Voyager was a Star Trek series I very much enjoyed but couldn't follow in my area religiously. Nevertheless, I still managed to catch every episode right up until around "Scorpion" where (I kid you not) the loss of Kes as well as de-emphasizing Chakotay made me less interested in watching the series.
Because of this, I haven't followed the Voyager Relaunch as well as I should have. I was, thus, quite surprised when I heard about Janeway dying in a fight against the Borg. It was a risky move and quite ballsy since she was the effective star of the series. I wondered, for quite some time, if they would bring her back. This is the book they do so. This isn't a spoiler since it happens very early in the text and is actually the biggest source of publicity for the novel. Much of the novel is centered around Janeway's return and this is the best part of the story.
The premise of the novel is Amanda Rogers, a one-shot character from TNG, and Q's son (Q Jr.) are discussing the fact Kathryn Janeway's death is a fixed point in time. This roughly means Janeway dies around this time no matter what else is happening in the Multiverse. This confuses the two Q since such a thing is oddly specific. It's as if the universe is out to get Kathryn Janeway. Meanwhile, the Starfleet armada heading to the Delta Quadrant (using its new Slipstream drive) gets itself into a pickle. Apparently, a really ancient race encountered something unpleasant and things steadily go from bad to worse.
As mentioned above, the Janeway parts of the book are quite good. Janeway's reaction to the developments in the Alpha Quadrant are underdeveloped but poignant for what little we see of them. Likewise, Chakotay's reaction to Janeway's return is entirely believable. I could have spent the entire novel following her as she tried to establish that, yes, she is the real Kathryn Janeway. Sadly, I feel there was a missed opportunity or two because I think Janeway should have taken at least a chapter to get used to the events of Destiny.
Unfortunately, I can't say I'm a huge fan of the B-plot. Without giving too much away; I feel it killed two underused characters needlessly, revealed too much about the nature of the Q, took too much time away from the resurrection of Janeway, and resolved a Torres plot I was enjoying in a very haphazard way.
I also am annoyed by the introduction of a race even more advanced than the Caeliar. Given the entire purpose of the Caeliar is to seek out other races more advanced than themselves, you'd think they would have noticed one in the Delta Quadrant. Which, given the Caeliar scan millions of other galaxies, is a bit ridiculous. Of course, I had the same question as to why the Caeliar seemed to have missed the Organians, Q, and other beings whose technology is more akin to magic than science.
Sadly, there's a lot of plots in this book I would have enjoyed more than the B-plot. For instance, the book revisits the group from "Unity" which I was hoping we'd see as a thriving gestalt intelligence. Unfortunately, that plot is nipped in the bud almost as soon as it's raised. Then, it's players are summarily moved off-stage when I was hoping they'd play a major role in the book. I'm also not pleased at Janeway reflecting on "Sacred Ground" having a scientific explanation when that was obviously just the Doctor grasping at straws.
The book does have an excellent handling of the Q continuum, however. I also felt the character of Q Junior was greatly expanded on, becoming a much better man than his father. Q, himself, plays a large role and I very much enjoyed his character. There's even a special guest appearance by Kes, which I absolutely loved. Watching the various Qs interact is also a treat, the omniscient beings trying to fool one another using methods that have to be seen to be believed.
This, however, doesn't compensate for the fact that Janeway's resurrection doesn't get the attention it deserves. This, despite the fact it's a book ostensibly about her return from the dead. The book prefers to focus on the origins of Captain Afsarah Eden, who is interesting but needs her own book to discuss the surreal story told.
In conclusion, I think it's an okay book but wasted a lot of its potential. Many of these elements may strike you as petty nitpicking, however, and you're welcome to pick it up to judge for yourself. You will still get your money's worth.