In your part of the country I don't think they do too much other than making sure they have enough food to make it through the winter. Some also will insulate and wrap the outside of the hives with tar paper. Up in Canada some have special sheds to move the hives into that are kept cold (but not as cold as outside) and dark all winter. Most everyone across the country will treat for mites to make sure that going into winter that the bees are as healthy as possible.
Out here we've got to worry about moisture and starvation. So I put what's called a candy board on top. It is about a 2 inch thick block of granulated sugar that was moistened and then dried out to harden. That provides emergency food (in those cases where its a long wet Spring) and it will absorb moisture (condensation) in the hive.
Bees raise a special type of bee int he fall that has a bunch more fat. These bees will live all winter, whereas a regular Spring/Summer bee will only live a few weeks.
