|picture courtesy of facecrooks.com|
Once you click on the Wall Post link, you will be directed to the page that asks you to install the "who deleted u?!" Facebook application. Then, if you agree to install the application, your account is now controlled by the application and you are spreading the scammer's message to all of your friends.
Therefore, never, ever install them. The scammer's end game is to get you to complete surveys or download games to your computer. Each time someone completes a survey, they get paid. These downloads often contain viruses, trojans or other malware. Don't compromise your privacy and security, and don't spam your friends with these bogus apps.