Many of the most popular applications on Facebook, including FarmVille, CafeWorld, and Mafia Wars, are created by a company called Zynga. Zynga's CEO, Marc Pincus, recently acknowledged that these games contain "scammy" offers, in which users are offered various deals in exchange for in-game currency. These offers, unsurprisingly, tend to be deceptive schemes designed to trick users into unknowingly signing up for unwanted subscription services, or download upwanted software. Zynga has pulled some of these offers, Facebook has suspended some applications, and at least one law firm is investigating a possible class action suit against Zynga and Facebook, as well as MySpace and several of the marketing companies responsible for the offers themselves.
When you allow a social media application to access your profile information, you open yourself up to a wide variety of scams. The more applications you use, the easier it becomes for tricky marketing schemes or malware to slip through. It's safest to avoid these types of games altogether, but if you just can't quit, be very careful when downloading files, clicking on ads, or agreeing to any type of offer. Be sure to install Internet security software on your computer, and set it to update automatically. And consider investing in an identity theft protection service, to help prevent the worst possible result of an Internet scam.