However, there's not much of a comparison. The iPhone Street Fighter uses pre-rendered 2D sprites based on the console/arcade game's 3D models, for a look reminiscent of Killer Instinct. The 3DS game, on the other hand, appears to use lower-detail versions of the actual 3D models, judging by the dynamic camera angles. That's why you get to see the extreme close-up of Ken's goofy punch face up there.
Of course, it's worth noting that these are early screenshots, and the final game may come out looking different. Given the relatively low texture detail, though, this looks like something that could be possible on a handheld system. Compare the two games yourself in our galleries.