Katy Perry says that when she moved out on her own, she started to meet people she'd been warned to avoid growing up.
"I was raised to say, 'These people aren't good, you can't be friends with them'. It doesn't matter whether they were gay or straight, just certain people in general. And I started to meet great inspiring people that became my best friends."
She's clearly not putting herself out there as a poster child for any kind of lifestyle. She says "I Kissed A Girl" is really about her own curiosity over a schoolgirl crush and something she explored in the song in a tongue-in-cheek way. (In fact, there isn't much that Katy Perry doesn't do tongue-in-cheek. She's a self-proclaimed prankster and takes very little, including herself, too seriously.)
She did thank her gay fans, and added that she is a gay activist, voting no on California's Prop 8. But like most of the other things she talked about, she didn't sound at all like she was encouraging - or discouraging - homosexuality. What she sounds like is a young woman who is exploring the world without trying to force her own journey on anyone else.
Good rejoinder here.