I think Leo was making the point that Lady GaGa broke the stranglehold that Rap/RnB/Rock have had on the US mainstream for far too long. I think a track like Timberland's 'the way I are' ,'sexyback' and Kanye's 'Stronger', paved the way for dance/electronic beats to permeate the mainstream. GaGa is the natural progression.
The thread was about the US, not anywhere else.
The future is so yesterday: A synth-pop timeline.