He used TATP...
"At any rate he looks more like a psychotic kid than a real jihadi."
I suggest you read the summary at my blog. I've tried to mention all conflicting reports, and have provided links to all sources for what I've mentioned. It will answer many of the questions you have been posing on this thread.
BTW: New information tonight. Former FBI agent said the the FBI received new directives after 9/11 to treat all explosions as Terrorism related until proven otherwise. My question is why wasn't this done in this case...
It was.