I loved the main character Wade and all his faults and flaws, I love the other characters, I love the general design/concept of the game, I love the absolute nerdiness, I love how thorough the back story is and how well put together the book is. It's funny, it's captivating and I couldn't put it down. It's all made even better in the audio book which is narrated by Wil Freaking Wheaton! (you may remember him from his reoccurring role as himself in the Big Bang Theory). I literally listened to this book for hours on end instead of doing anything else, because I just couldn't stop myself.
In short: this is really good. If you even have the slightest inner nerd or interest in anything from the 80's you should read this - or better yet, listen to it.
P.S. They're making a movie out of it and Steven Spielberg has signed on to direct!