Oh man, without a crystal ball, I don't think anyone knows the answer to that question. That being said, anything around the BeltLine is a bit of a no-brainer. However, this is where everyone is looking right now. I see North Atlanta up to Cherokee and Bartow Counties being great appreciation plays. Really, you could probably drop a pin on a map of the Atlanta MSA and land in a neighborhood that will appreciate well over the next ten years (barring a massive recession on the back-end of that timeframe).
Sorry I do not have a better answer for you but that's because there just is not one, other than "Nobody knows."
Feel free to reach out anytime if you have other questions or ever want to chat about the Atlanta market!