You have to recognize the continual creativity of identity thieves and scammers. They tend to use the latest or most popular social networking sites and features.
The Sophos blog recently reported on a new threat in Facebook status messages that takes advantage of a feature we all want on Facebook but doesn't exist. The phishing status messages you should ignore and not click the link:
"Get the official Dislike button NOW! http://bit.ly/xxxxxxxxxxxxx"
In the above example, I masked out the shortened website address. This will vary, but you get the idea. If one of your Facebook friends fell for this scam, then you will probably receive this phishing message:
"I just got the Dislike button, so now I can dislike all of your dumb posts. LOL! http://tiny.cc/thedislikebutton"
If you click on the link, your browser will be directed to a fraudulent Facebook application that accesses the data in your Facebook profile, sends spam to your Facebook friends, and encourages you to complete a bogus survey to help the scammers make money.
The Dislike button scam was bound to happen as Facebook and website operators expanded their use of the "Like" button and Facebook social plugin modules on websites across the Internet. And, this was not the first scam on Facebook. Earlier this year, scammers circulated a free Walmart gift card status message. Walmart does not ask consumers to complete online surveys for free gift cards. It is wise for consumers to learn how to recognize phishing scams, including these scams on Facebook.
A reminder: the Facebook "Unlike" button is real. You can find it in the lower left-column on Facebook fan pages you have already liked. This is the valid, official method to unlike a fan page. You can also find it beneath a status message or comment you have "liked."
[Addendum: Mashable reported a coming change in the display and behavior of the Facebook "Like" button making it more difficult for Facebook members to "Unlike" something.]