The character often referred to as another demonic power rising, that we eventually come to know as being named Lilith, was just called 'he' several times before we ever met her.
This is bugging me, for the obvious reasons. It is most likely because they didn't know who the big bad evil demon was going to be, and they used a generic He for the character, but it bothers me that the people flocking to her side wouldn't know what gender she was.
Those things can naturally be fluid, what with possessions, but Lilith strikes me as being of the generally female side of the coin more often than not. Maybe she was temporarily in the body of a male during those few months before we saw her.
Eh, just a little niggling thing bugging me I wanted to ramble at no one in particular, because I know no one is listening. =D
Edit: Watching "Jus In Bello" now, and Ruby strongly corrects Dean when he says "he" instead of her. Interesting...