Actually, cnn bites

.
The scenario you describe would be considered spam, because you would be posting the same link in multiple forums on this site, most of which would have no relevence to the link.
If, on the other hand, you posted a link to a story on CNN that was relative to a particular forum in that forum only, then it would not be spam.
If you are not sure what is spam you can always e-mail the moderators and ask, but I can assure you that board members around here, don't take kindly to people "posting a link and leaving", and people who post the same link in multiple forums tend to be mocked mercilessly.