I have a bad feeling that in trying to explain how much I loved this book, I'm going to spend too much time on just how gorgeous it is to look at – with photos of some of the places they visited, receipts from various diners, and pages from a travel book Amy's filling in one state at a time – and not enough on the wonderful main story. So, before I start rhapsodizing over the way it's put together, I'll just tell you that Amy and Roger are fantastic characters, the people they meet are sweet, funny and quirky in their own ways, Amy's fear of cars and the start of her recovery from her guilt after her father's death are very well-portrayed, and the descriptions of the places they visit are great. Apart from anything else, going into too much detail about the plot would risk spoiling things – this is definitely one where you want to find out where the detour takes them as you read it rather than beforehand.
So, onto the complete loveliness of the way it's put together – stunning. The travel book pages, motel reservation slips, and similar things add to the story wonderfully, especially towards the end, the photos are beautiful, and as for the playlists… wow! If you're a big music fan the time taken to read the book will no doubt be dwarfed by the time taken to check out some of the hundred plus songs the pair listen to while driving, ranging from Amy's musical theatre highlights, to the Britpop of Oasis, to hot new artists like Owl City to the more obscure such as Someone Still Loves You Boris Yeltsin. From what I've managed to track down in the few hours since finishing nearly every song sums up the stage of the journey it's played at brilliantly, adding even more to an already superb book.
Huge recommendation, as you've probably worked out.