Speaking on the subject of paying off publishers for exclusivity, Tretton told Joystiq "[Sony] invested so much money in the [PS3] hardware" that it simply "can't write checks for exclusive software."
While popular theory is that Microsoft paid Square Enix off for its recent handfull of upcoming releases, word around the industry campfire points at a decision made by Square Enix months ago to focus on multiplatform development that saw Final Fantasy XIII land on the Xbox 360. With a high install base and solid attach rate for the Xbox 360 in North America and Europe many developers are forgoing exclusivity in order to lessen the blow of "next-gen" game development. Capcom has been a prime example of this point with Devil May Cry 4; which saw better sales on the Xbox 360.
Regardless of the situation, Square Enix is happy to bring the experience to as many people as possible and as gamers we all should be too.