I don't think Sony really wanted that large a change for the PSP-2000, they wanted all PSP games to be playable on both the 1k and 2k models, moving the stick to the other side would make older games play weird.

Lets hope that this tactile feedback touchscreen comes through for the next really new model of PSP, if all teh face buttons and anolog sticks were digital we could drag and drop the where we like. Though how a digital anolog stick would work I have no idea...