those post pretty much cover it. but i'll add my 2c
I live in northern suburbs so can't comment on the southern places as I don't make it out there much, but I hear there are some excellent spots.
I have been to the following
Swallow at the hollow
smokejack
KC Pit
Spiced Right
Dreamland
Pig n Chick
Old Hickory House
Shane's rib shack
Fatt Matt's
and a few others I can't remember off hand.
I think my top favorites are Swallow, KC and smokejack Wife loves KC, I think because there sides are consistent, but Swallow is better IMO, maybe because it's in walking distance
I've only been to Fatt Matt's once and think its ok, flavor was good, but I like my spare ribs trimmed, and there was ALOT of fat on them, sides were good. I'd try it again.
Spiced right is ok, I don't like their sides at all, but like the meat is consistently good and I like their sauce.
My least favorites are Dreamland (too much salt on the ribs) Pig n Chick (didn't like anything about it) and Shanes (more like fast food, but it works when I need a fix for lunch).