Atlanta is made for driving. It's spread out all over the place, the public transportation is negligible (by the time I get to a MARTA train station, I'm 3/4 of the way to work). And it's especially not made for walking. Long city blocks with no tree cover combined with the heat (which I may have mentioned before), sidewalks that look like they've taken mortar rounds, or often, no sidewalks at all.
But perversely, that can make walking more rewarding. You end up seeing Atlanta from a perspective not normally used, and you pick up many things often missed.
Back in Boulder, where the temperature is always perfect and all the people are beautiful and there's always rainbows and smiles, I walked a lot. When I moved out here, I initially lived in one of the lacking-sidewalks areas; there was a bar about 50 feet down the street, on my side, but I had to wander out into a six-lane road to get to it. Once I moved down to the Highlands, I got back into it a bit, and over the last few days, thanks to the 2006 Greg Commitment to Health, I've been doing it a ton.
And no one that doesn't have to do it, does it -- you'll have the streets to yourself. Off the main shop/restaurant drags, you don't get asked for money because the homeless guys figure you must be nuts if you're walking in Atlanta.
This morning I headed down to a few neighborhoods I know little about -- Cabbagetown and the old Fourth Ward. Didn't see much of either, but cool sights abound (this tower, f'rinstance -- no idea what it is, never heard of it. It appears to be opposite an old train station, but no clue). Up around the hip Krog Bar and Rathbun's, there's shells of old buildings (as above).
An Atlanta-native friend once bemoaned the city's relationship with its history -- saying it was only too happy to pave over everything unless it can be turned into a profit. That's largely true, I fear, but if you get off the main roads, get away from Peachtree, it becomes less true. There's a hell of a lot of cool old shit out there, and some of it's doing a good job surviving.