2013-05-09: I read a copy of advanced chapters for the Calgary Wordfest volunteer reading program (http://www.wordfest.com/), this was the recommendation I gave. 
 I have previously read books by Tamora Pierce, including her books which preceded this one and introduced the main characters. This story serves to fill the gaps of some storylines that are alluded to in the other books in the series, and is a direct continuation of a previous book Street Magic. I think this book could still be read by readers unfamiliar with Tamora Pierce's work, but the exposition at the beginning is slow moving and may not be entirely engaging. After the introductory chapters, the motivations of the characters become more apparent and the plot begins to unfold. 
 This book takes the main characters to a new country that resembles China during the dynastic period, but in a fantasy setting. Much of the text is world-building and explaining the surroundings and differences of this new setting. Also, there is a clear divide in classes amongst the characters. The protagonists are visiting the imperial court with high ranking figures, including the emperor. The protagonists are not necessarily from wealthy backgrounds, but by virtue of their talents, they are treated well while still being seen as outsiders by others. Pierce demonstrates political intrigues with the inclusion of a captured prince from a neighbouring area who is kept as a slave by the emperor. 
 Older elementary readers or junior high readers might identify with the younger characters, from whose point of view the story is told. The initial chapters seem to set up some conflict for later in the novel, so there will presumably be action scenes. Battle Magic will appeal to readers who enjoy the fantasy genre and also fans of Tamora Pierce's previous books.