Confirmed Gateway are using a kernel hack to gain full access to hardware. SD card access definitely wouldn't be possible without it.
So I'm wondering what's stopping them from using the flashcart as a loader to load games off the SD card? I guess they don't have the knowhow to do so yet.
It annoys me a bit that they're basically putting an exploit into a flashcart just so they can sell hardware that shouldn't even be needed to begin with. I understand that they need to make money, but if the flashcart was only required once to install the hack onto the system which would then let you load games from the SD card without the flashcart inserted at least it wouldn't be as annoying. They could even sell it for more money since people would likely be hacking their friends' 3DSes meaning potential lost sales. I'd be willing to pay more for something that is only needed once and is usable on multiple consoles.
That said, the cart is looking a lot more useful now that it's proven you can save in multiple games and swap MicroSD cards no problem. All it needs now is a GUI which will take a lot of work building a library that can access 3DS hardware and display graphics.
But, unless they can discover a new exploit that works on newer firmwares, it's not going to have very good game compatibility as games start forcing updates newer than 4.5. They're just lucky games and consoles haven't started shipping with 5.x.x yet.
Well, here's a big fuck you to everyone who said there was no point in staying on 4.5 because the kernel exploit would never be released.