Thought this might be of "interest" to some on this board (no pun intended). AA is offering no payments for three months on flights that cost under $200 and no payments for six months for flights over $200 on the new AA credit card (different than Citi AAdvantage). The rules seem to allow the card to be used on RTW tickets as long as there's an AA flight it's plated on AA stock. Just make sure to pay it off within the three/six months or you will get dinged for interest from the date of the charge. But if you pay it off w/i the three/six months, no interest.
AA Credit Card Promo Link
AA Credit Card Promo Link
Well, I applied last night, even though I ended up not using it. Got the same limit as my AAdvantage Mastercard. I noticed that it seems the card is being underwritten by Citibank, which makes sense since they have everything already in place. So maybe someone with a higher Citicard limit would be able to get a higher limit American card. The "cost", of course, is that you don't get the miles for the purchase. But the saved interest for the six months might be worth the miles. Might. 
wonder how the purchase of a rtw on aa stock in a foreign country would work? would one have to pay a 3% foreign currency fee? if so, that negates the interest free loan period it would seem.