I think it's most likely an exclamation that means "wow!" My son reads the "Wimpy Kid" series and as the books are popular among 8-12 year-old boys, I sincerely doubt it has anything to do with Zooey Deschanel or the book Bruce suggested. If you tell me which book it's in and what page, I can raid my son's bookshelf and check it out.

It seems that Alexis Nelson's book title, “Zooey Mama Special Like Me” is a way of showing how the daughter speaks. It is a very "childlike" way of speaking and thinking. It shows the difficulty of the daughter. So, when the sentence is used by others, it is self-referential or self-deprecating. It suggests that we are "developmentally disabled". Adults sometimes adopt this Baby-Like manner of speech to express themselves. For example, I might say to my companion; "Me hungry!" or "Bruce Hungry". Also, in the comedy movie, "Blazing Saddles" several of the characters voice lines in this same manner. Example: "Mongol says; "Mongol like Sherriff Bart!" It imitates precisely the kind of developmental disability that author and mother, Alexis Nelson refers to. I might also say to adopt the same disabled communication style; "Bruce like Junior. Junior Bruce's friend.." It is a fact that people from English speaking countries often play games with their language. They will adopt any expression that they want to get a laugh.

It's a comic strip from the series "diary of a wimpy kid"

it’s from diary of a wimpy kid as far as i know it has no connection to the book others have mentioned but i could b e wrong

There are also other movies which exemplify this developmentally disabled and childlike pattern of speech. In the movie "Short Circuit" (1986) http://www.imdb.com/title/tt0091949/ A robot is portrayed in exactly the same manner of a "disabled development." The speech patterns the Robot, "Number 5" expresses when it talks, is a direct mimicking of that speech pattern. It is a ME---LIKE---YOU kind of thing. .