Nih: Safeweb is an anonymous web browsing service. Basically when you use it, you can't (easily anyway) be tracked down.
BD: Being a racist prick, threatening others, attacking people for their beliefs, and spamming the Feedback forum with the ability to post as a guest (earning the official safeweb IP ban) sound like good reasons?
I think he was banned within a few hours of his registration and most of his posts moved, so you probably didn't see him fly by