It all depends on how you look at it Nintendo bases their games and systems around the family, or kids. So the DSI beats the PSP in that department because you dont see games like God Of War And SOCOM on the DSI.
But also you have to look at the PSP the same way. It appeals to the teen, young adult group. You think we all wanna see mario, and cooking mama on the PSP? no we wanna see blood, swords, grenades and guns. There are more features on the DSI than the DS but they appeal to kids, The PSP has video, music, customization is down to a science.
So all in all I think they beat eachother in their own house. But since i have to choose, im going PSP because i have one.
PS: the DSI will go further in marketing because of the family oriented pitch, but the PSP is more versatile
