Mostly age. In some cases, vintage, since the green-and-black label distributed here states "6 Years Old", while it contains no age statement elsewhere. The white-label is NAS (and, thus, almost certainly 4 years old); the gold-and-black sounds like the very appeciated Very Rare Old Heaven Hill 10-year-old.
...Also, because I live in Minnesota, I've only seen Heaven Hill bottled in bond with a gold and black label. While in Kentucky, I saw a white label; green label and a black label, and it seemed, a couple of other label variations. What are the differences?