I absolutely LOVE this casting! I’am glad that AMC and the producers of the show took their time with this and waited to find the right guy. Negan is such a fun character in that you love him while hating him. Unlike the Governor who is a sadistic and completely insane killer, Negan is sort of a cool jock whose had his murder-knob turned up to the max because of the ego he has gained from being the alpha male of a bunch of crazies. He has a presence. He is a cold-blooded murderer with a handsome-charisma that makes him hard to hate. And his way of looking at the post-apocalyptic world he lives in is not necessarily wrong. He is a survivor like Rick, though he prefers to rule with a righteous iron fist.
Jeffrey Dean Morgan can completely pull that off. He is ruggedly good looking with a famous actors charm. But he also has the ability to play a man on the edge, that can turn aggressive instantly. This casting has hit it right on the head, with a barb wired bat.