Banning books aloft?

Boing Boing: TSA screener: 2-book max on flights. Ross Mayfield has an interesting conversation with a TSA screener in which the screener mentions that the number of books to be allowed in carry-on will be decreased from four to two. Is this simple confusion between matchbooks (which would make sense in the context of the rest of Ross’s conversation) and literature, or does the TSA actually think that books are possible hijacking weapons? My money is on the former, but it’s too good a story not to share.