One of the best things about JoJo is that she doesn't have any sort of gimmick or pretense to her, as many popgirls do today.
She's a very down to earth, and naturally cool girl. You get that vibe from her immediately, and people are drawn to that. I know I was when I was 13 years old watching her interviews/videos. I think that everyone in the industry she comes across gets that vibe, too, so she's well liked.