What if they're smarter and have a better way that nobody knows about?i doubt the eshop idea will work the games are drm , when you dl them the eshop most likely reads the sn or esn or some other hash of mac and other # to get a console id of your system and then encrypts or drm the games so they will only work on your 3ds, you cant just swap folders on the an sd and expect it to work, you would need to decrypt then remove the drm and resign for your console i think at least if there smart that how they would do it
Actually, the ticket system that Nintendo uses is pretty similar to what he said.
I'm guessing that the 3DS sends its unique console ID, the eShop issues a signed, encrypted ticket tied to that ID, and the 3DS downloads the ticket, authorizing it to use whatever software.
How about backing up the SD card contents from a DSi, then transfer those games to the 3DS via the option under Settings? Then, you could copy the files from the 3DS SD card to a computer. Because the DSi's game was the original, could you set the DSi as the original and the 3DS version as an encrypted version? Nintendo could just be messing with our heads so much with the 3DS by itself that they forgot to check their cross-platform transfers.
Edit:
What about this?? I own one and have an idea for it below.
http://www.memorex.com/en-us/Accessories/Gaming/Universal-Game-Selector-Case1/
It is able to work cross-platform and is recognized by all DS variants (except DS "Phat"). Also, when a 3DS game is inside one of the slots and is plugged into a DS/DSi, the older systems will say that there is no game inserted, yet a regular DS game is. That means that there might be code inside that determines what is and isn't allowed, like an ON/OFF switch for older systems.
Maybe there is some code inside of the hardware that could be direct access to the 3DS cartridge slot??? Then someone, like Neimod, could reverse engineer that code and develop a bootloader that will allow 3DS mode.