I heard something like that. But like you said, it's not publicized. Only the international data add-ons for smart phones are. Still not bad. The $24.99/20MB will do for me. It can be added and removed at will and will be prorated also.
AT&T International - Wireless from AT&T
Phones: Iphone4, HTC Inspire, Nokia E63, BB Curve 8310
Sim cards: AT&T (Contract), Tmobile USA, Virgin UK, TelnaMobile, Ekit, Yackie