generally speaking, you won't get an email notification of a new virus, nore would it be worded in such a fashion, since, let's face it, who's going to be sending unsolicted email to you just "FYI" if you follow my meaning. Virus checking companies aren't going to get much out of it, and your friends and family are unlikely to write emails in the style of language used. (nor are professional companies either, just to stress the point)
Generally speaking the message *is* the payload of the virus itself, and is further spread by people attempting to be helpfull. Sad state of affairs, however, as tim said, there's no harm in trying to be helpfull.