Lovely city. You will have a nice visit, I'm sure. It is nice to walk around the squares admiring the old houses. One thing I really like about Savannah is that it was a planned city, with proper squares and streets that make sense (unlike my beloved home city of Charleston, which bewilders even the residents with our sudden one-way streets).
Another thing I think is interesting is that all of the mansions are of different styles, so you get to see a real panorama of design in one place, also unlike Charleston, where the "Charleston single house" reigns.
There are good eats all over town, and don't forget to check out the beaches as well.