great question!
we use tumblr, twitter and facebook (this case just for suggestions and to keep our users updated, we do not put any porn videos neither photos).
regarding pinterest we tried as well, but they closed our account due to some erotic picture, you have to be very aware on what you show there, as matureisland said just "glamour, bikini.."
Then nothing to do with Google + :p
i do not know much about reddit, anyone can tell me a bit more
? maybe its interesting for us to be there too
thanks all!