I understand some of the post saying Brit's vocal performance is not 100% invested...
But really I think it was the best way to tackle that song and to give to the chorus that relaxed, ethereal & "I don't give a damn" attitude which contrast with the lyrics and thus makes it more interesting.
Another funny critic also, is that she should be screaming her lungs out in the chorus (and she's perfectly capable of such thing before you try to use the usual "she can't sing" accusation).
Well those who are giving this "advice" are also calling this song "generic" without realizing that even though the song isn't, it would have been if B's team had followed their idea. You sense the irony ?
To answer more briefly to the subject of the thread, Katy was influenced by Ke$ha.
All of her songs sounds just like some tracks/demo from
Animal which is a shame because her first album's singles were way more interesting than what she's reduced to now.
Did Ke$ha influenced Britney's sound ? I don't mean to be rude but you just don't know a lot about pop music & music if you think she did.