To me, I've lost three friends because they didn't want to be a brony anymore. And online, I've lost ten-fifteen. They all said "the show is stupid and boring", "I've lost interest" or "Princess Twilight is a dumb idea."
I'm not telling them to shut up @poniesforfun, I'm telling them to get over themselves if they think Princess Twilight is a bad idea.
Our community is a family, and we can't just drop each other.
I personally don't think the fandom will fall, but people are leaving, and more will.