Even though this is targeted to young adults, I can say with certainty that any adult that has ever played a video game, watched cartoons, or read comics will vastly enjoy this book. It's just so much fun to pick out all the archetypes he paid homage to and poked fun of.
I actually decided to create a page on TVTropes for the series, and there are so many that I spent a lot of reading downtime looking them up and listing them all (and was scolded by the author to just finish the darn book, haha!). But don't think that means the book itself is cliche. Even though elements of it are familiar, the way they are combined creates a unique and new experience.
Lastly, don't pass up this book because of lack of vampires. This book technically has more vampires than any other book in the fantasy genre. More vampires than you can shake a stick at. Seriously.
I got through this book really quickly and giggled out loud quite a few times during it. I loved the social commentary but also the fictional story of the world about to fling itself out of orbit and one determined person willing to step up, rally together all the misfits, and save everything from being destroyed.