Saying RIGHT NOW that Sony is stealing hardcore handheld audience to Nintendo is...just stupid. There's no other word to describe this.
For the casual audience, it's a whole different thing: now, many of us ( myself included ) are pretty convinced 3DS won't do the same numbers as DS did, but between being like the DS and between like the...err, N64, there's an entirely different world. Certainly, Ninendo will probably do all its best to reach the most people possible, they won't surrender. Right now, we can just say 3DS will probably be "just" a great success for them, not a cultural phenomenon like DS or iOS right now. iOS is a cultural phenom now, not a fad like the Wii wasn't, it's attracting most of the casual audience which in the past would have selected Nintendo. Just, we don't know if this audience can accept to buy another device, a gaming specific one. Time ( and Iwata's moves ) will tell us what will happen, and it's going to be VERY interesting.
...But about the "hardcore" audience, right now...come on Pachter. Come. On.