The characters are well realised and the dragons, in particular, are beautifully written and well wrought. The relationships they have with their riders is particularly interesting and Novik's dynamic is well thought out, if perhaps slightly flawed. The conflicting natures of the dragon corp and the navy are well illustrated and set out, with the navy perhaps winning out slightly over the dragon riders in terms of discipline and kindness.
If the book does have a flaw its that the twist is too obvious; it really didn't come as a surprise to me.
All in all though Temeraire is a charming read.