My daughter says that they are very specific about sexual orientation on Tumblr, with all kinds of minute twists - m to f trans but asexual, pansexual versus bisexual vs omnisexual (not sure the dif), largely straight but open to other experiences, etc., etc. It's very interesting to me to hear the way that teenagers see sexuality and gender in such broad, rich ways I never imagined. When I was a teen all the gay kids were in the closet and if there were anyone leaning trans I'm still in the dark about that.
Interestingly, her friend who teachers her art is a very popular senior. I only met her briefly and she was dressed in jeans, t-shirt, but my daughter says that often she dresses very femininely at school. I think that's a damn radical shift in the world to have a trans kid be so popular.