This will come as a shock to the porn fans here at FR --who haven't shown up yet for some reason. ;-)
I would be more apt to blame MTV and sleasy "reality" shows where sex partners are auctioned off like cattle. This is presented to children as acceptable behavior. At least most kids know porn is "naughty" and they shouldn't be looking at it, unlike the soft porn of "Sex in the City" that gets showered with mainstream awards. Don't get me wrong, porn will screw kids up but I think the root causes are broadcast TV and cable.