I thoroughly enjoyed reading Mad Ship, and despite its length got through it fairly quickly. The plot moves at a good clip, and many of the problems I had with Ship of Magic are gone from the sequel: there's less bloat, and the overall arc of the trilogy becomes clear, as do the roles of Paragon and the serpents. Even Wintrow (my least favorite character in this trilogy) was better here.
And yet, certain plot contrivances keep this book from getting four stars. The biggest one is the mission several characters undertake to rescue Vivicia. The chances of that particular plot working out are so farfetched that I didn't believe for a moment the levelheaded Vestrit women would agree to it, and so it seemed that Hobb swept all the characters' common sense under the rug to get that particular plot. Additionally, this is the book where several main characters all improve their personalities, and while there's certainly an explanation for each individual arc.... how is it that in one book, Malta grows up and loses her mean streak, Brashen loses his drug addiction, and everyone (including Etta herself) forgets about Etta's propensity to torture people? Hobb does characterization well, but I just wasn't entirely convinced.
Overall, though, I don't think this is a bad book. It has a fun, exciting plot with well-developed characters. The world is rather bland and under-described, but it's not cookie-cutter fantasyland by any means, and the larger political situation and the characters' personal stories are well woven together here. I would certainly recommend this book to those who enjoyed Ship of Magic, and even if you were on the fence, in my opinion this one is better.