The emails try to emulate the general look of notifications sent out by Facebook, and are titled "Your friend added a new photo with you to the album":
The recipient is purportedly being contacted because he or she has been "listed as close friend", and is urged to view the photo in the attachment.
Unfortunately, the attached New_Photo_With_You_on_Facebook_PHOTOID[random].zip file contains a piece of malware detected by Sophos as Troj/Agent-XNN.
The malware is a backdoor Trojan that copies itself to C:\Documents and Settings\All Users\svchost.exe, then adds itself to the Windows registry in order to be run every time the PC is booted.
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