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As we've explained previously, these scams typically propagate themselves by downloading malware to your machine, then blasting messages to all your friends - either to spread the malware further, or to drive traffic to spam sites, or both. Facebook has become increasingly good at blocking these URLs as soon as they become an issue, hence the "link" you'll receive (seemingly from a Facebook friend) isn't hyperlinked, but has a space between the site name and the dot-com.
If you receive such a mail, just delete it. If you find your account is sending these mails, run a full virus/malware scan, clear your browser cookies and change your Facebook password.
Have you received one of these Facebook spam mails today? Let us know in the comments.