I have had the pleasure of following Julie's career since was a self-proclaimed "wannabe" writer. I even got a chance to read some sections of this novel in its infancy when Julie and I shared a critique group. Since I heard the news about signing her agent, and then landing a contract with St. Martin's, I've been eagerly awaiting this book. 
 This book is a lot of fun, Julie has some interesting time travel theories, and the treatment of teen relationships is honest and open without being vulgar. (That is to say, there is some pretty frequent and casual discussions of sex that actually match up to real-life teen experiences.) A few reviewers mentioned they were confused about some of the time travel scenes, but I found it very well-organized and easy to follow. 
 The best thing about this book was its main character, Jackson, who is one of the best male narrators I've ever read in a teen book. He is the only character with any significant development, though. Some of them, like Jackson's father, I found completely unbelievable (nevermind somewhat misrepresented in the book's blurb). 
 The book really needs more ironing out. There are some problems with the plot, the ending was predictable and a bit emotionally contrived, and as I mentioned above there is only one really good character. All in all, this book is pretty typical for the genre. 
 Recommended for teen boys and people who like plot-driven stories, and have a VERY strong suspension of disbelief.