Whats MOST important to me, is not graphics or things of that nature,
But the control layout. Nintendo and Microsoft (xbox) have always won in this department for me (Excluding Wii). if my hands arent comfortable, i'm only going to play for like 3 minutes before i put it down. the PSX/2/3 controller with the stick placement and what-not is just awful for me. it's harder to aim then trying to use the X/O/Triangle/Square buttons to look. I'm not sure about this 3DS stick (i know its not called a "stick", its more of a slider or something...But its a stick lol.) it's placement way up there worries me that it will be a bit hard to reach or require my hand to be up higher, almost on the top screen. I don't think sticks are meant to be on handhelds.
Anyway, the 3DS i think is going to feel better in my hand than anything Sony could come up with, and i think we're going to see a lot more games for the 3DS than the PSP2, Game developers like working with new tech like they did with the touchscreen. working with the PSP is like asking a developer to port their high-end PS3 games to the dreamcast, with no innovation.
The moral of the story is, Don't do drugs.