Allow me, someone who works in the music industry, to comment:
OK... what sells more: a confident person who believes their own hype, or a person who acts timid and down to earth?
Katy Perry, who happens to be a nice person (I met her at a party in LA) is a brilliant pop songwriter. She does not have the greatest voice. She is attractive. An attractive, great song writer who can sing decently equals star status these days. Look at taylor swift. Great song writer, good looking, manageable singer. With the studio magic that goes on today, its not hard to make average singers sound good. If you want an example, lets take a look at these vids, and listen:
1:35-1:40 that is pitch correction (not the same as auto tune), same with 2:01-10
now that you know what to listen for, look for it in this katy perry song. I'll give you a hint, it happens on the first note sung out of her mouth.
every high note, that i assure was not *perfect* when they recorded it, has been corrected.
They are both brilliant songwriters, good looking, and decent singers. its a formiddable combo in the music industrry. Katy perry has written songs for kellay clarkson and pink. that was her industry *in*