IF, recent rumours about PSP2 specs are true, the handheld is really a monster capale of PS3 like graphics. Something like PSP and PS2.
But, this time around, 3DS is quite powerfull too, not as much as PSP2 rumoured specs, but it can pull off some effects that belong to the HD twins and even puts the Wii to shame, the best example we've got is Resident Evil Revelations. That game looks pretty decent for a portable.
At the end of the day, weve got two portables that despite having a big difference on hardware specs, on a tiny mobile screen, many impulse buyers, misinformed people, casuals, etc may be confused about which one is more powerfull.
This situation gets worse if you add the 3D effect in, it really makes the 3DS look like something really high tech, and the graphics look better too. It fools people into thinking the system is more powerfull than it really is.
This time around, the graphical difference isn't as obvious as DS and PSP, and publishers might very well know that.
So my question/prediction is: 3DS and PSP2 will share multiplatform titles and those will push 3DS pretty hard, and despite being already good looking games, it won't use many of the PSP2 power because of its multiplatform nature. They'll look basically the same game, but one console has 3D and the other doesn't.
Think about this like current HD multiplatform games that got a PC version too, and despite its good look on consoles, it could look way better on PCs, considering PC's are pretty much already one generation ahead, but no specific games pushing for that hardware power since it doesn't make sense to do so.
