I don't want to get into the plot much since I will most likely let spoilers of the first book slip if I try to go into any detail. This book differs from the first book in that it focuses a lot more on some characters other than just Vald. The adventure follows Prince Andrak on the mission that he and his sister set out upon. We also see more from Kyle and Thorgast as they attempt to help Thorgast's people.
Personally I would have to say that I did enjoy the first book a little bit more, but I think that is because I really enjoy Vald as a character (not that there is anything wrong with the others, but I do play favorites) and this book did not feature him quite as much. Robert continues to write wonderful action scenes and describes his massive world in the right amount of detail. You do not spend pages reading about each mountain in a huge range, but visual images are made clear by his descriptions. His webpage is also an excellent tool having all kinds of extra information including some excellent maps to help you see the journey everyone is taking.
The only downfall of the book is that since this one just came out I'm sure there will be a decent wait for the next book in the series. Excellent work again Mr. Day.