Kim, the best known active South Korean in the sport may have lost 3 of his last 6 bouts but his heavy hands and aggressive style have helped make him a fan favourite. In fact his style has seen him become a mainstay on American TV with ESPN picking up most of his recent fights (including this one).
Whilst Kim is great fun to watch he is technically limited and if his power can't take an opponent out early doors there is every chance he'll be shown up. This may be the case against Herrera who has proven himself to be incredibly tough and hard working. In fact it terms of single wins Herrera's victory over Ruslan Provodnikov stands out as the best either man has to their name and his ability to take Provodnikov's power (and even the power of Karim Mayfield and Mike Alvarado) doesn't bode well for Kim.
If Kim can manage a win it's fair to say he'll be back in the mix for a world title, though a loss here could well see him put a long way from the world title scene. Oddly a loss may actually do him a favour for now with the current world champions all having solid technical boxing skills that would neutralise Kim's own strengths.