In reply to RCR81.

Adele has success because her tone is enjoyable and she sticks to the same formula. She does not have the range or artistrty to compete with Christina. Christina wrote gems on Bionic, Back to Basics, and Stripped that Adele could never write. While you say she's "all over the place", I see it as a diverse pop star. And that's the point: Christina is a pop star. Reinvention comes with the territory. Adele and Celine aren't pop stars. Sticking to the same style every album works for them. But Adele could never see Christina's level of artistry and creativity or possess her range.