Yes, while this kind of stuff doesn't help either party much in the long run, you do have to admit to chuckling a little at the end when Andrew confessed to sending WP's co-founder's wife an empty box instead of her order.
edit: Yep, sorry, I was not clear, the kind of chuckling one does when a business freely publicizes an act of stupidity that could cost them customers.
If by chuckling you mean, "Ensuring I never do business with this company in the future." The open letter makes them come across as jerks. The P.S. makes them look like assholes.
edit: Yep, sorry, I was not clear, the kind of chuckling one does when a business freely publicizes an act of stupidity that could cost them customers.