The books works mostly as three intertwined novellas rather than as a single overarching novel, which lends itself to the feeling of a more complete work.
The novels starts off agonizingly slow, following yet more Abominationists. I nearly gave up on the book as this section bored me. Meanwhile, we have a romance begin between F'lessan and a green rider. (This is not a spoiler because the book makes it very plain that these two will be shacking up at the end of Act 2). About a hundred pages in, the novel finally gets some Pern-like momentum, with yet more disasters to show the studliness of our dragon riders. The B-Plot of the Abominationists continues, dragging the plot whenever it shows up. In my opinion, the entire B-plot could get dumped with no harm to the work.
I feel like one plot thread was left dangling. I had expected that Toric would finally get his come-uppance, eventually getting himself exiled, while F'lar and Lessa would have finally decided to retire south, but neither of these two plot threads came to anything. My guess is that both were in the original plot outline, but length considerations and manuscript delivery dates cut those threads shorts.
Expect to see some and all your favorite characters. If you haven't read a Pern novel before, don't start here. You'll see character both prevalent and obscure rear their heads, including those from short stories and B-plots.
Thanksfully, most of the plot talking-head scenes tend to stay on topic and actually progress the plot, rather than just suck down air.
My understanding is that there's some vigorous discussion on the dragon abilities discovered in this work. I find that this yet-another-discovery is no less contrived than all the other contrived discoveries of the Ninth Pass, so it works well enough for me. I've already accepted teleporting telepathic dragons. What's a little more unbelievability?
Even with all its flaws, this book still works better than most of McCaffrey's non-Pern books, the ones where she didn't have strong editors or supporting writers, especially those written in the aimless 90's. The book will scratch your Pern itch, or drive a stake through it's heart, or both.