I think users of reddit still approach it like it is composed of outsiders (even though it isn't). For example plenty of people I know use the site but people don't talk about it like they would twitter. Using twitter is a sort of normal social network. Reddit is treated far more analogously to a tv show that some people like and others don't.
Of course I can't really back this up with anything as it is just a feeling.
It's bigger than Twitter was in 2012. Could you imagine a journalist in 2012 calling Twitter a cult website?