I think this is all related to the recent upgrade that ensures the wii deletes any unsigned data stored on the Wii itself. They will open up the SD card slot and this will become an extension of the internal storage.
The Wii will probably ensure there's a set amount of free space on the internal memory itself and when you run the SD programs they will be copied to the space and ran from there. This will ensure they run faster and if any hackers try to copy files then unsigned or incorrectly signed data will be removed.
By constantly updating that signature via firmware updates then they can trigger the Wii to clean up any time they activate the trigger.
But hey what do I know - I write call centre software and thats a million miles away from these solutions.







