YASSSSSSSSSSSSSS!!!!! Satellites you have been redeemed.
P!nk should be mentioned, but at the same she shouldn't. She has just as many hit singles as Beyoncé and Britney yet her songs are always more famous than she is. She is one of the best charting female artists on Pop radio so you'd think think she'd be on the Britney or Beyoncé level but she's far from it. I like P!nk so it's rather strange and unnerving she's never reached that level. :-/
I think Avril Lavigne OWNED the so called "pop-rock" sound this decade.... Since Avril came out Hilary, Lindsay, Lillix, Ashlee, Brie Larson and so many acts tried to have her catchy "Let Go" sound but failed..... Even 30+ Liz Phair "Avrilized" herself lol.
Let Go is way different than Autobiography and it didn't fail it also reach the # 1 thing that Avril failed!
the queens... 
I think of Lady Gaga as more of a faze or era...