Both are amazing looking system, but which would be better. Well all and all it depends...........
3DS- My friend has it and I have played it, and although I was dissappointed to find it was depth and not actually pop out at you 3D, it is still cool. Although, as of now, the games are rather, well bad on it, besides Street Fighter 4. Although, some games it has lined up for it are looking great, Legend of Zelda, Kid Icraus, Metal Gear Solid 3, both Resdient Evil games, the Mario game, Donkey Kong, Kingdom Hearts, and many others coming out. And the graphics far beat that of the Wii, which is good for a handheld. Although, the down side, could it become a causal device? Also, after long periods of play, it could possible hurt your eyes after a while. and battery life, not very long for a handheld. And the cost, it cost only $100 to make, and yet they sell it for $250, more then the Wii when it firsted launched.
NPG- Well, lets get one thing straight, for a handheld, the graphics that they showed and promising are amazing. And so far the games look great, Uncharted, Killzone, Metal Gear Solid 4, Resistance, Little Big Planet, and other amazing looking games. As of know, if you want mainly action games, this system is were you will go.The design, a great edition of the 2nd analog stick. Also most of the games listed are launch title games, meaning a good start for it. But the bad side, so far, all the games are mostly ports of PS3 games, do I really want to spend X amount of money for games I can play on PS3. Also, battery life, the PSP already has really bad battery life, and then add on top of the great graphics, and it will shorten it even more. And, could it follow the down fall of the PSP, or will it be able to maintain good enough games to keep it alive? And of course the price, because we all know that when the PS3 first launched it was "599 US dollars" so who knows how much they could sell this for.
Winner- Niether, for it really comes down to, what do you like better out of the 2. both, even though for it flaws, seem amazing, it just truly depends on which you want more.