A suburb of Atlanta, Georgia. My roommate in college (who is from Atlanta) called it "the drug dealer capital of Atlanta." An illustration of the sort of people you can meet here: he went to a Popeye's chicken and stood in line. A guy was in another line, and my boy saw something shiny in his mouth. He struck up a conversation, and dude dropped the bling bling and smiled. In his mouth were gold teeth stencils which spelled out "STEADY MOBBIN". He said, in classic ATL accent "Ya like dat, don't you dawg." (The omission of the question mark is intentional. He didn't ask it, he stated it with the clear expectation that his teeth were the shiznit). I seemed to meet a lot of women with finger waves here.
Decatur can be used as a metaphor for anything ghetto fabulous.