If I ever do get into My Little Pony: Friendship is Magic enough to where I will want to brag about it (the same way when I've first seen both Star Trek The Original Series and The Next Generation), I would call myself an "MLP-Fan" and not "Brony". To me, a Brony is a racist, sexist, homophobic (if it doesn't involve lesbianism, but still a double-standard), transphobic, etc. sack of shit who self-worth themselves over a fucking show for girls and slams anyone who isn't into the show. Not only that, most of them look like shit and those who don't look like shit are douchebags in fedoras and whatever accessories that scream "don't date this asshole".
And then, there are anti-Bronies. Don't get these words wrong. It's okay to dislike MLP:FiM (for example, you don't find it "cute" but "annoying"), but do realize that "Ew, it's a girls show" is illegitimate criticism when you're into works like Super Mario Brothers, Pokémon, etc., as those are for kids, who you're most likely not. What I'm saying is you're slamming fans of a show because it's not aimed for them when you like works that isn't aimed for you. Ugh, I'm so sick of people dismissing a work and being totally ignorant about it at the same time, and I'm equally sick of this "love and tolerance" meme these hypocrites smear around.
Because that fandom has gone to hell, I reject the "Brony" label (and again, I haven't gotten into the show yet), the same way I reject other labels like "Furry".