Genres do exist because frequent users of any large bookstore can instantly tell what any piece of fiction is supposed to be about by its title, its cover and its location in the shop.
Sentiment: POSITIVE
I see genres as generating sets of rules or conventions that are only interesting when they are subverted or used to disguise the author's intent. My own way of doing this is to attempt a sort of whimsical alchemy, whereby seemingly incompatible genres are brought into unlikely partnerships.