I finished up River of Stars last night. I highly recommend it to authors and readers both - Guy Gavriel Kay has a distinctive, and very well-crafted style, and I love to read the work of those who use language in new and interesting ways. I am in a strange subset of those who have not read a great part of GGK's earlier works, so my review, unlike many others, will not focus on a comparison. 
 What I enjoyed: Without spoiling too much, the story focuses on the interweaving between past legends, current events, and future legends. Our main narrators are, by and large, figures whose stories will be written in legend, and they have a sense of this: they wonder how history will portray them, understand the larger moral implications of their actions, and, in a very human way, both believe passionately in their destinies and doubt themselves utterly. The narration follows the defining moments of their lives, both in terms of events and in terms of thoughts, and the writing style echoes this: lyrical, stream-of-consciousness. Kay does, in my opinion, an exquisite job of placing us in the viewpoint of the narrator. The book is worth reading for this alone. 
 Further, Kay has described the world of Kitai excellently through a patchwork of vignettes from the perspective of minor characters. With protagonists that are so influenced by the social norms of the world around them, this style of world-building is an elegant way to frame our heroes' fears and motivations. 
 What I enjoyed less: Plot and pacing. If there is one flaw to River of Stars, it is the plot arc - and to be honest, I am not sure I can think of it, unequivocally, as a flaw (more on that in a moment). Kay speaks in the epilogue about the liberties he took with a particular set of historical events, compressing the stream of events and shifting things around somewhat, but the plot still meanders somewhat. In a very broad sense, it follows the traditional fight arc, but there are times when, chapter by chapter, it seems to be in a holding pattern. On the other hand, this wandering, this back and forth, this unclear path to success - all of it serves to provide doubt and fear to our heroes, and that is the piece of the book I most enjoyed. 
 Overall: I highly recommend this book. It is a true joy to read. More, I get the sense that the author truly loved this book. I can find no better way to describe it: he crafted every word of it. The whole book breathes love, as one might find with a little wood carving or a baby's quilt. And that was beautiful to see.