I LOVE those ads, especially Extenz. They all feature some bimbos and a jag-off in a lab coat talking about enlarging "that certain part of a man's body" without ever specifying which part of a man's body they're talking about. I think it would be awesome if it turned out to be the forehead or tongue.
Anyway, the reason why they are so vague is to get around FCC regulations about false advertising (I've worked in marketing for years and have seen this sort of thing before). You can say the word "penis" on TV (albeit only during certain hours - as silly as that sounds) so if the pills really worked they could say "enlarge a man's penis." The careful wording is so they can't get sued when someone wastes money on a scam.
There's never been a verified, clinical scientific study that showed that a combination of herbs, vitamins, hormones or testosterone is effective for permanantly enlarging the penis. In fact of those supplements can be unhealthy.
Man, I am Captain Buzzkill this weekend...