Let's put this matter to rest right now: Any Facebook application that offers to reveal who is viewing your profile is a scam. Period.
Security research firm Sophos posted a memo saying a rogue app that was spread on Facebook recently with messages like "OMG ... I can't believe this actually works! Now you really can see who viewed your profile!" is bogus. I've asked a Facebook representative about this before, and he told me that apps on the site do not have the ability to track who is viewing profiles.
In this particular case, clicking on the link provided in the message takes users to a Web page that encourages people to permit an application to access their Facebook profile. Nearly 60,000 people have fallen for the latest scam, based on figures from Bitly using a search on one of the URLs used in this campaign, according to the post.
For more on this story, read No, you can't see who viewed you on Facebook on CNET News.