I don't know where the Centurion cards are made, but I know the rest of them come from First Data in Omaha. I wouldn't be surprised if that is where the Centurion cards are made too.
By the way... Does anyone know why it is made out of Titanium to begin with? True story... Oprah complained that it kept on breaking, and if American Express wanted her to spend money like it was going out of style and use the AMEX card to do it, then we would have to make it out of something a little more durable. She didn't necessarily suggest titanium, but it was her request that got the higher ups thinking about how they could be truely unique and offer another interesting feature of arguably one of the most elite cards that is available to Americans. That doesn't mean the card doesn't have a whole host of problems though. Some vendors have declined to accept it because they didn't think it was real because it was made of metal. It has caused problems in airport security lines. It doesn't fit in gas station pump credit card thingys. The list goes on with minor pains in the rear that using this nifty card causes. I think the benefit outweighs the irritation though.
I want one just so I can have concierge arrange for me to compare a hot and fresh Chicago pizza and a New York pizza side by side while sitting on the beach in Miami.