Suicide, porn, and more have all happened on live stream sites before. But I'm sure that the likelihood of inappropriate content has skyrocketed with the launch of console streaming, whose younger audiences are often lacking in foresight.
Inevitably, the mainstream media is going to blow this up. They'll accuse the Xbox and PS4 of being "webcams" that will allow your kids to be preyed upon by internet predators, etc.
Everyone's been so concerned about the ratings of games that they've overlooked how much more problematic and potentially dangerous the console cameras/streaming potential can be.