The recent "Battle of the Books" match-up between Shadow Country and The Disreputable History of Frankie Landau-Banks has caused some debate around the YA blogosphere; see Liz B.'s post and the comments there attached for some enlightening discussion.
I won't vote since I haven't read Shadow Country but I like the way the debate bares the fundamental question about the difference between books for youth and books for grownups: is there a difference and what is its nature? To my mind, it's this question that keeps children's/YA lit as a genre perking along and it's only when we have it answered that we'll find ourselves in trouble. (As far as linking children's and YA books goes, that's a question answered by publishing history.)
Here's a corollary question. What if Frankie had been published as a book for adults? As crisply observed social comedy, the book has definite cachet within its genre, and its nomination for the National Book Award was both deserved and no surprise. But what if it wasn't YA, simply undifferentiated (category-wise) fiction? I'm guessing it would have lost to Shadow Country without a murmur or reproach. The fact that Frankie is a YA book gains it a certain recognition (both within and without the YA walls) it would never get otherwise.
I've been listening to Sissy Spacek's stunning reading of To Kill a Mockingbird, another book that provokes the what's-the-diff question, as it is a book published for adults now mostly first-encountered by adolescents. I read it in fourth grade and not since; what's striking me now is how much I missed being more allied with Scout-the-child-subject than Scout-the-adult-narrator. I remain glad to have read it at nine but it's very much an adult book.
Let's leave the question of just how stupid this kind of book tournament is for another time. SLJ is going to be running one this spring and I've said I'll judge a round (just because it's stupid doesn't mean it isn't fun) and will let you know what it's like.