Y'know, I'm just gonna go out on a limb here and play Devil's Advocate for a moment. Just a moment.

[b]#1:[/b] This is [b]fantasy[/b] being played out by adults. Nobody sane goes raping people, but rape fantasies aren't uncommon. Nobody wants to get fucked by tentacles in real life, but there are people who enjoy that shit all the time. Last I checked, nobody was running around burning Hentai for fear that it might inspire people to rape Japanese school girls and attempt to make sweet love to the local Zoo's eight armed octopus.

[b]#2:[/b] Most people who are not completely insanely retarded will just go look up what BDSM is after they watch this movie and inevitable stumble upon this kind of safety information anyway. The people who want to jump right into a BDSM relationship because of this movie without even looking up what it is, would have done so based on any other influence anyway.

[b]#3:[/b] This is a mediocre book by an author that is genuinely surprised that it got anywhere near this popular being made into a mediocre movie for people who want to explore a fantasy.

Really that's about it. People worried that this will spread misinformation about BDSM should realize that even a cursory Google of BDSM, especially related to this movie, will bring up all the things wrong about how it portrays it and how safety is emphasized and so on. In fact, I'll just go on and say that all this movie is doing is making BDSM more mainstream, which makes it more culturally acceptable to talk about and explore, gradually, as the social barriers erected against it are slowly chipped away by even this mediocre crap.

Do I think this is going to be a good movie? No. The source material was pretty meh. The movie will be pretty meh. It'll be forgotten about in five months.

Stop thinking this'll create a sudden rash case of horrible rapes and abusive relationships. This won't, at least, not to any degree as to make it remotely worth the time of being a legitimate concern in comparison to lack of education and societal intolerance of the entire subject matter altogether.