These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Some people note her subverting general acknowledged 'Facts' of Rap and Pop music as evidence she is smarter then she says. (Boots + Boys, Blah Blah Blah, Got A Pear, Dinosaur, Sleazy, Crazy Beautiful Life, Kiss N Tell to name a few)
"C'Mon" is just a catchy, happy, wonderful dance number.
Broken Base: There are still many people who can't decide whether she is the real thing or if she is a parody of party-girls. Among those who both believe the latter and dislike her music, there are many people who can't decide as to whether this makes her more respectable or less respectable.
While she has achieved success in her native United States, she is particularity popular in Northern England where her music and act seem to be taken more seriously. In many areas like Greater Manchester, she has influenced female fashion, standards of behaviour, and become somewhat of a cultural icon.
A lot, but the song "Mr. Watson" probably takes the cake. The entire premise of the song is an Ordinary High-School Student who wants to sleep with her history teacher, and not just "I think he's cute" kind of stuff. It comes about as close to saying "I want to have sex with you" as you can without actually saying that. Not that some people might not think that was hot, but just... ew.
"Mr. Watson I want to get with you" and "Teacher whatcha gunna do/Cause I am coming on to you." "I want you on your bed, or on your desk." I'm pretty sure that counts as flat out saying "I want to have sex with you."
She actually does say, in the background "Mr. Watson, I wanna sleep with you".
For some, Ke$ha herself. She could be attractive, but she always looks like she just woke up in a dumpster.