Can sony cancel the usb feature?

[dunno001]

Can they? Yes. Will they? Not entirely. I'd actually not be surprised if they require some sort of data check, or even require the external device be in FAT32, with its 4 GB file limitation. It would allow them to keep all the features of photos, music, movies, etc, and block out large images like a BR ISO. They also may allow the system itself to back up larger things, encrypting a code unique to the system to play the back up, be it a DVD, BR movie, or PS3 game. But doing that lets files into the wild that would show the encryption and key access, so I don't see that happening...