This scam also apparently has nothing to do with the Facebook account named Dislike Button, which has garnered more than 3 million fans. There's proof I'm not alone. That would be comforting, if I wasn't such a curmudgeon. Heck, I'd even settle for an "Indifferent" button.
(FYI, click the photos tab on that Dislike Button page you'll find many pictures of extremely underdressed women with captions directing you to their various porn sites. And you wonder why I'm cynical.)
To recap: Yes, a Dislike button is a fine idea. But not that Dislike button. Remember, there's a reason "Facebook apps" rhymes with "crap for saps."