I noticed that thread on AN/I and thought perhaps people were being too dismissive. We should follow the lead of the folks who are professional in these areas and not take the decision upon ourselves, i.e. report what we can and allow police/school administrators to decide whether a particular threat is credible. A quick e-mail to school administration that a threat was posted using a school IP/against a particular school takes little time and prevents a news article saying "Wikipedia ignored threat, 27 died."
Nathan