The winner is a book that's already proven this point by being accepted as a genre-crossing modern classic: China Miéville's The City & The City.
To selfishly quote our own review from earlier this year:
To put an end to the vagueness, here's something specific. The City & The City is easily the best book I've read this summer, and possibly this year. Its genre-bending classification will invariably frustrate booksellers and award lists alike, but this is a new classic of any... every... classification.
What Miéville has done is simply this: take a simple creative idea - the stuff of any magazine story or Creative Writing 101 - and make it into a mind-bogglingly delicious novel. And the intricate plot? The empathetic character? The philosophical progression? He does those as extras - Miéville casually includes what most authors strive - and fail - to achieve. That's crossing the line from skill to genius.
We'd both like to think that we recognized this book as something special since we first opened it. At the very least, we can solemnly say it was our favorite of the year, and the winner of our first Kitschie. Congratulations to China Miéville.