I remember being in IRC chatrooms and having predators galore trying to get me to hang out with them. From my understanding, the problem hasn't gotten any better.
A parent would be smart to limit some internet access to their children. We ID at bars and brothels (where legal), the way I see it, the day my son is willing to learn to jump through hoops to access pornography is the day he is ready to watch pornography. I'm not all too concerned about them working around these things, but I'm concerned about easy unrestricted access.