http://tv.yahoo.com/news/mermaids--nons ... 09947.html
Author of the article also seems inclined to think it has possibility.
Anyways, Animal Planet aired a couple of shows. One called "Mermaids: the Body Found" and it's sequal "Mermaids: The New Evidence". Basically showing a bunch of actors pretending to be scientists and doing a show about how mermaids are real and being hidden by the world governments.
Its an interesting show that shows how mermaids could have happened, and how they could have evolved and came to be in the first place. I found it entertaining and knew it was just for shits and giggles, but I guess I shouldn't be surprised some people actually believed this show to be real.