Mario Kart Facebook Scam: It's a Trap!
There Is No Mario Kart Facebook Game: It's a Scam
If you get an invite from one of your friends to play Mario Kart on Facebook, do not click it. The text of the invitation reads: "Play Mario Kart on Facebook with your Friends! Join the multiplayer mayhem NOW! Click here to play” and “AWESOME!! Mario Kart is on Facebook! Use the link below to join my Team if you decide to play"
There is no Mario Kart port for Facebook. Instead, if you click, you'll get taken to (yet another) survey scam designed to steal your personal info. Don't get played.
Note that this isn't a "Facebook virus": it's a social engineering attack, in which the user is tricked into willingly giving up control of his or her account.
A funny aspect of this scam: it promises victims an iPhone 5, which of course does not exist. Sophos has more details on the scam, but all you really need to know is, don't click it.
If, for some bizarre reason, you actually went through the scam-survey, change your Facebook password immediately, since your account is already spamming your friends.