The author must have had a really fun time writing this. It strikes me as more lyrical and poetic rather than novel-y. You get some plot, but this book could have easily been an epic poem with no plot at all. The structure reminded me a lot of traditional fairytales (which are alluded to in the end). None of the characters are particularly multi-dimensional which is true of many fairytales in which the characters are archetypes rather than "real" people. The circus and the reveurs also made me think of the world of Fairy and the myths of human heroes and princesses crossing the threshold, eating Fairy food, and then not being able to assimilate back into the world from which they came. 
 I liked this book more than I thought I would. I definitely see why it turns up as a suggestion for adult Harry Potter fans so often. "The Night Circus" and "Harry Potter" both have in common a fantastical magical world with so much specificity, imagination, and fun. I typically prefer novels that have more plot and character development than world-building and detailed descriptions of scenery, but I enjoyed the artistry of the language. This is one of those books that you know will be made into a movie, but deep down you know it shouldn't be because what makes it special is the writer's ability to stimulate all five senses with just his/her words. If put into the right hands, it could be a magnificent artistic film, but more likely some film studio will try to turn it into a blockbuster directed by Tim Burton. 
 The only part that I wasn't satisfied with was Isobel's storyline, but overall I liked it!