I have an adult related domain and site that doesnt host porn or porn links. Its an affiliate site for lingerie and also online adult 'goods' shop. They dont show any nudity on the sites either, though some of the lingerie is revealing.
Several of the pages are indexed in google and are deemed as safe. I cant host adsense ads since they are meant to be 'family friendly' sites to host adsense, but when I did a FAQ search in adwords for adult sites (which is an area I'm starting to look at, till now all traffic has been natural), apparently the ads are reviewed and classified accordingly and then ads that fall into the adult category are supposedly placed in adult related content sites (which confuses me as you are meant to be familiy friendly to host adsense...unless they have changed it? Or directed more towards direct search queries).
I also looked at setting up a profile/promotional page on FB once but the response I got back was along the lines of 'Sorry we dont cater to your kind of site' (adult), so its a bit of a mixed bag I think (I might try doing that again and see if anythings changed lately).
So I would think that FB would have gone by either (or combination of)the domain and keywords of the site to come back with that response and if they do, then there are definite risks other automated programs might as well.