In my jurisdiction, incest is only criminal when it comes in three forms: parent/child, grandparent/child, and siblings. As far as I know of these fandoms, that means Arrested Development (cousins) and Lost (step-siblings) can probably be counted as 'soft incest' rather than 'incest proper', if we want to get down to it. Pseudo-incest seems to cover it pretty well. Not sure about the other fandoms mentioned... Is incestfic becoming a bigger thing now that the shows themselves are latching onto the idea?
Oh, I didn't really mean to suggest it was 'mainstream'. Fairly certain that this would never become mainstream per se, I just didn't know how else to put it.
More public awareness? More fanon heading in this area?
Twincest, I have to say, is really intriguing. There seems to be an overwhelming sense of narcissism in that 'ship, because it's hard to tell when you end and ther other person begins. Well, that's what I got from the few fics I've read, anyway.
The thing with "slash", though, when it started out, was that it didn't
just mean gay. It had a far more deviant undertone to it as far as I could tell - very UC - perhaps because at the time gay relationships
were considered very deviant. There has been discussion about whether, for example, Willow/Tara fics from Buffy can still be counted as slash, because it is not only gay, it is also now canon. Now that a great number of people are considering gay relationships to be normal/canon, the "slash" label seems to have lost a lot of its original meaning. In steps incest and it's like how slash used to be. That's how I see the 'new slash' statement, anyway.