It's down to choice. Players who want to play existing games with better graphics will choose PSP, but those who want to be surprised by new things would prefer DS.
Harvest Moon is coming to Wii too, which does focus on new gameplay...
Wada: Yes there are plans for Wii, and you'll obviously be able to use motions with the Wii Remote to perform actions like watering the plants or ringing the cow bell to call your cows near to you.
But I would like to emphasise that the core attraction of Harvest Moon is not in the control mechanics but in the game concept. I don't want people to get carried away about the controls...
But what separates Wii from its competitors is its controller capabilities. If you're not placing emphasis on controls, why was Wii your console of choice for the next Harvest Moon?
Wada: It is simply because the types of people that are into Wii are the typical target user for Harvest Moon.
In hardware terms alone, if I were to choose a platform for the best playability in Harvest Moon I would choose PC.