I want to say Ke$ha but I realize that her 'genericness' sometimes surprises me especially The Harold Song. I don't think anyone can replace what she's done so easily. Whereas I believe someone could redo Katy, although I like her and her music. Regardless, that must mean that generic music is that way to go because Katy has been snatching some wigs! :O
And no offense to Xtina fans but her music is bloody awful. Beautiful is the only good song I like of hers.