My prediction is he will take a few days off and then "up the ante" by getting specific.
He's going to target a name cop or reporter to demonstrate he is not only capable of shooting random passers by.
It seems to me that before the shooting that the school, the spokescritters were saying over and over that the schools were safe. The most recent attack was practically under the nose of a police officer.
Need I say that this shooter is trying to show a stunt-like shooting? I think that you may be correct, Travis. The shooter may be Al-Qaeda, but he's beginning to show a personal interest in showing off. Of course, that just makes it all the more effective from the Bad Guy's point of view...