It's not that this is a bad book. Far from it, in fact. It was a real page-turner, and I ran through it at a brisk pace. It just left me feeling somehow unsatisfied.
The book takes the form of a mystery. Right from the start, we are presented with the problem: that Kahlan has vanished and nobody other than Richard remembers her existence. We then follow Richard's attempts to try to find the cause of the problem, in the face of doubt and occasionally open hostility from his friends.
While a fairly decent story, it lacks the urgency and sense of wonder that characterised the earlier books in the series. It seems as if Goodkind wrote it simply for the sake of writing something, rather than because he felt he had to tell this particular tale.
There's also more of the moralising that has become a common occurrence in the series, with Richard seeming to act as a mouthpiece for Goodkind's own political and moral ideologies. If you've enjoyed those elements of the preceding books in the series, then you get to enjoy more of the same. If, like me, you find them preachy, then you have to sit through more of the same.
That said, this is a definite step up from the last couple of books of the series. The author has indicated his intentions to end the series within a couple more books, and there is an indication here, especially with the cliffhanger ending, that the last two books may see him back on form.
Overall, if you've managed to get this far through the series, then this book is definitely worth reading. On the other hand, if you gave up earlier on in the series, and want to know if Goodkind ever gets back to his brilliant best, then the answer is sadly "not yet".
And if you're new to the series, don't even think of starting here. Instead, go and check out the superb "Wizard's First Rule".