This isn't the first of Canavan's books that I've read, but so far I like it best. Her most recent series before this--the Age of the Five--started fine but ended up awfully dry. This time she manages to keep a solid pace throughout.
You can't help but like the MC here: the daughter of a peasant/physician, skilled herself and thrust into a higher level of society unexpectedly when she suddenly shows signs of being magically gifted. She's brusque, irreverent, talented and intelligent--but Canavan manages to keep her from being too much of any of these in particular.
The setting is also lively, starting in a village on the outskirts of society, moving into the Big City, then sending us back out to the woods and eventually past the mountains into a different land. That last step seems to move a little faster than it should, taking away some of the enjoyment of visiting a new society. And the setup for the sequel is definitely likewise truncated, but not so badly that the rest of the book isn't worth reading.