Ok, here's the deal straight from the city of Atlanta.
The good:
Mild winters, it's easy to ride year round.
Cheap compared to the tristate area. (My wife's parents were able to pay cash for their house here because of the equity from their NJ house.
Great college football

The Bad
Smog alerts nearly everyday in the summer.
Traffic, imagine trying to get into NYC without the LIRR. I can't stress how bad it is, a coworker spent an hour and a half to travel 16 miles today.
This may or may not matter to you but you can't buy beer or wine on Sunday at the grocery.
Summer heat and smog can make riding tough

McDonough used be a nice little town. Now it's definitely suburban. They have half million dollar homes sprouting up everywhere. Georgia's not bad but if I didn't live here I wouldn't move here.