I don't have any actual evidence, or experience with the product yet, but the impression I get is that there's a whole ROM chip that denotes the region of the unit as well as the unique ID for networking purposes. This is in addition to the flash RAM that gets updated with new operating system code.
If my impression is correct (and take it with a lot of salt because I don't know for sure) then any region swap would require a donor ROM image. And then you'd be able to play games from other regions, but online functions would be unavailable to you. This would be like all those PS2 emulators that fail DNAS network authentication because Sony's network sees too many duplicate consoles online that aren't supposed to be there.