She was a bridge between the more 'serious' female pop/rock singers appealing to older audiences (i.e. Alanis Morissette) and the female pop stars appealing to teenagers (Britney/Xtina etc).
Kelly and Pink are good, Kelly especially, but they have nothing on Avril.
Avril >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>>> pink >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >>>>>>>>>>>>>>>>>>>>> kelly