This is really a 3 1/2, but I liked it enough to round up. The Night Circus
is an atmospheric, slow-paced novel. It is as much of a mystery as a fantasy, as we don't learn until about 3/4 through the book what the competition entails. I think the book lost a bit of steam around that point--from then on the driving force was the romance, which was obviously going to be some kind of doomed, even if they did end up together.
The characterization was a bit thin, but it actually worked the way the story is told. Going deeper into the characters here would actually have detracted from the story somehow I think. I feel about The Night Circus
kind of how I feel about Jonathan Strange and Mr. Norrell
(which I have yet to manage to finish): I loved
the world-building but the pacing was just glacial.