I've read a few reviews, and I think some are too critical of this book. I love a good story, and a new story in the Pern universe is always welcome. Some have criticized that Todd takes liberties with Pern canon, especially when it comes to "timing" it, which wasn't introduced by Anne until much later. Todd uses it in this book, and I think he uses it well, and logically. There is even mention that the harper should "forget" the old songs that mention it, and I believe that is likely what happened. It was forgotten in the many Turns between this story and Lessa's use of it in the later Pass.
I love a story that is well-told, and I believe this one was. Although it took me a few chapters to get into it, mostly because of new character introductions and the setting was a mining camp instead of Hold, Hall, or Weyr, I enjoyed reading it all the way through, learning more about the watch-whers. And now I look forward to reading more stories set in this time on Pern.