Obviously, we'd all like some more information about the attacker. The fact that he was a foreigner from the Balkans makes us wonder if he was doing this as a terrorist attack, but it's less obvious than if he were carrying an Egyptian passport and was obviously arab.
Certainly this type of attack wouldn't be something orchestrated by bin Laden. He goes for the more spectacular stuff. In the overall scheme of things, this is pretty small potatoes.
My own guess is that this guy had mental problems. If he is a Moslem, then perhaps he was literally on a Jihad and doing his part to kill Americans independently of any outside direction.
But it's also completely possible that this guy was a simple nutcase, and the repeated asking about the time seems to bolster that, in my opinion.
Perhaps he wanted someone to get suspicious, tackle him, stop him. It'd be a way to avoid having to go through with it, yet still retain "honor". The equivalent of attempting to get through a metal detector with an obvious gun...you gotta suspect that they want an *out*.
Great, now I find I don't want to say what I'm thinking. What time is it?? Can I have your seat?