The reason GaGa is as successful as she is is not just down to her talent. Certainly Christina is just as talented - her voice has a wider range and more power than GaGa's, but GaGa has written or co-written all of her songs. However, the really big difference is work-rate - GaGa just puts more effort into her work - when she releases her next album later this year it'll make 3 albums in 3 years compared to 5 (if you count Mi Reflejo) in 11 years for Christina. Christina has released 14 singles in the US in those 11 years (plus don't forget her last number 1 was back in 2000!) - so far GaGa has released 8 in just over 2 years - and then there's her absolutely crazy concert schedule - I've heard other artists complain when they've done a tenth of that number. GaGa simply has a greater hunger for success than any other artist around and she is prepared to work as hard as she can to achieve it.