The term "terrorism" is usually taken to mean an attack on civilians, though as a legal matter, this is far from settled. This definition would exclude the Fort Hood shooting, where the targets were soldiers. In any case, the bet is over non-state, politically motivated killing, which is broader and would include Fort Hood, I think.
FWIW: The targets at Fort Hood were soldiers, but predictably-disarmed soldiers. In the area Hasan attacked, the soldiers he shot at aren't allowed to carry weapons or even have them within easy reach. So it's more analogous to shooting up a bar frequented by soldiers that takes your weapons at the door.
Plus, his attack was intended to spread terror, not to achieve a military objective (any weakness he inflicted on the army capability itself was probably a secondary goal).
I would like to propose this as a thread for people to write in their predictions for the next year and the next decade, when practical with probabilities attached. I'll probably make some in the comments.