Developers have said that a 2D game made for 3DS could use the extra processing power not used rendering 3D to churn out nicer graphics and better physics.
3D games essentially have to rendered twice - once for each eye - which puts extra strain on the processor. If someone chose to bin the 3D effect, that game could potentially look better.
"Developers working on the system say that if they were developing a 3DS game that didn't use 3D, they could theoretically use the extra processing power for additional texture passes and more complex object and environment geometry, or even up a framerate from 30 frames per second to 60," reports IGN.
But could Mario Kart, which runs at 60 frames per second, run at a mighty 120fps in 2D? No, as IGN explains: "There's no benefit to raising a frame rate from 60 to 120 since the LCD displays of the 3DS (as well as the DSi, DS Lite, DS classic, Game Boy Advance...even the PSP) are limited to 60Hz."
Would you really want developers to start making 2D games on the 3DS? We think Metal Gear Solid: Snake Eater 3D look amazing enough.