I know I am a relative late-comer to Supernatural (I have in fact bought and watched every single episode now), and I know that some of the long-term fans hate the metafandom factor, with Chuck and his books and Becky the smitten slasher and all that....Some think it's insulting, disrespectful, etcetera (I'm not active in the fandom exactly, this is mostly what I get from Fandom Secrets).
But OMG I love it. It slays me. Trembly fangirl coming face to face with the physical reality of her favorite characters? Fanboys in self-shitting terror at the mere possibility of the reality of a Monster-of-the-Week episode, and yet still rising to the challenge anyway?
It speaks to me. In a good way. In a husky-heavy-breathing-whisper kind of good way, because there is nothing that gets into my pants faster than humor that resonates.