Now we're getting somewhere. A native NES Emulator for the iPhone has been released.
A Youtube video demonstrating the application is available. Appears a little slow at the moment, but certainly functional.
According to the release notes: "Presently there is no sound, and the emulator is a little slow (most likely due to the way I'm drawing onto the screen). And the control is a bit iffy (using an image of an actual controller, while cute, sucks)."