As we have all been observing Prince the last five years, he has been steadily playing in an oldschool funky-santana style with a side dish to soul and rock.

However, I found it interesting (highly) at the GMA performance that his guitar suddenly shaped its sound into Camille-era fashion. You will notice the style Prince incorporates on Lovesexy, but definately SOTT/The Black Album is the start.

Its a sort of evil sound. I would describe it as Jimmy Page but utilizing scales in a chord a touch past or prior to the root. Either that, or its an effect that does it for him.

Shed me some light.
[Edited 6/19/06 1:19am]