The author's significant education, research, and knowledge of the history and languages of the era set this tale apart as very unique historical fiction, a great accomplishment. Here's a short quote from the author concerning her book. (The quote is taken from her website.)
"Esther’s Song presents a realistic fictional account of Esther; the Jewish queen immortalized in the Bible book bearing her name. This historical novel imagines how a Jewish orphan, adopted by her cousin Mordecai, successfully navigated the lethal corridors of a royal harem, withstood palace intrigue, and overcame religious persecution to marry Xerxes, King of the Persian Empire, and save her people from extermination at the vengeful hands of Haman the Agagite."
While I really enjoyed this tale, there are just a few cautions I would add. First, there is at least a single scene which could be disturbing to younger readers. This book should be considered PG-13, or so. It's important to mention, though, that the scene in question serves a definite purpose. Her decision to include it was likely the right one, but it's still disturbing. Second, as I have also been told regarding some of my own fiction, this work could have really used some additional editing. There are issues of missing commas, "insure" rather than "ensure," the use of distracting American colloquialisms, as well as some problems regarding how the passage of time is conveyed within the narrative.
Even considering the preceding paragraph, however, this is a book I recommend you go and buy straightaway. Read The Song of Esther, and you'll find yourself reading the book of Esther shortly thereafter! It's a wonderful work of creation as well as research, and it really brought this important woman out of history for me, making her real and present in my mind.