FireDragon-16
Chelsea
That is a good question. I am not a medical professional, so I may be incorrect here, but haven't we seen various states of decomposition? For example: When Shane was killed and turned into a zombie last season, obviously, he was "fresh", for lack of a better word, and thus, didn't look much different than when he was still alive. Thinking back to this scene, I remember Shane's eyes looking very milky, almost like cataracts had sent in. Other than that detail, Shane still looked his typical grumpy self. In contrast, the zombie that was crawling on the ground from season 1, was very much in a state of decomposition. In fact she didn't have any legs (Remeber her? She was the first zombie Rick encountered after leaving the hospital, before he met Morgan and his son.) If I am off base here with my response, somebody let me know. I don't claim to know everything, in spite of my wife's arguments to the contrary!
I think you're completely right. I think how they look all depends on how long they've actually been a zombie. Plus the fact that we've already agreed that they've been moving through the winter months and the cold would have a definite effect on the changing of skin...