My least fav. only because of her little attitude - snapping the fingers and bobbing her head. The self ego stroking the judges will do at times gets old...but was mostly Paula and now Kara. I don't care if she's "hot", she's getting annoying and apparently needs to sit closer to the stage than the other judges because she always has to lean half across the table when she speaks.
I can take Simon's crass behavior because the vast majority of the time - he's accurate and sometimes the single voice of reason.
Ellen is fun. She really doesn't have skin in the game so to speak, but I like her quirky behavior and it offers a different perspective.