The girl in Idaho who was talking to this kid printed out some of the converstations as they started to become very specific as to what he was going to do. He told her of the burglaries, very specific information about the guns, where he hid them and specifically what he was going to do with them. He told her about making bombs, what he had and what he was going to do with them. His attack wasn't about "blowing up the school" as it was using pipe bombs to kill people with.
If you look at the escalation of his conversation, the video tapes, and the other evidence it is clear that he is a sociopath. These things are exactly, and I mean exactly, the same things the Columbine shooters did, acted, said. In addition his behavior is exactly the same as the majority of attack killers. He had the means, the ability and intention to carry out his attack.
Besides the obvious charges of burglary, receiveing and concealing stolen property, a bunch of other weapons charges, a number of conspiracies. I think they are also going to hang domestic terrorism on him.