Microsoft seems to be planning a worldwide availability at launch this time.
The Inquirer further claims the graphics part of the Xbox 360 will be superior to the PlayStation 3's, of which we heard two days ago that it may only be as powerful as the GeForce 7800 GTX. But Sony does have a better CPU but it will take some time before developers learn how to use all seven cores effectively.
The ATI R500 based Xbox 360 chip will be able to do 4X anti aliasing without a performance penalty while Nvidia’s part in Playstation 3 wont be able to deliver such a luxury.
You have to bear in mind that ATI chip has 10MB of very fast EDRAM, which is going to speed up things massively. Right now, Microsoft is telling developers to use at least FSAA 2X for all of the games, while most of the games will be shipped with native FSAA 4X games and will look pretty good.