Katy is here to stay
she doesn't need to prove anything, TD was such a smash era, her 4th single is doing so good!
"California Gurls", "Teenage Dream", "Firework" were #1 on the BB Hot 100, digital songs, RADIO songs and multiple radio formats. not to mention "Cali Gurls" was the biggest worldwide song of 2010.
I'm not sure about Ke$ha
IDK her single choices has been safe and it's getting old :-/ she needs something different... altough "Blow" is about to smash.