I was hoping someone would post a GA map, I knew I could count on you! I'm guessing you have Obama winning more rural counties because Romney is a poor fit for Georgia Republicans. I think he'll pick off a few rural counties but maybe not enough to really make a difference. If Obama improves it'll be mainly because of a better performance in metro Atlanta.
I agree on all the metro counties voting for Obama, but if I had to choose between Cobb and Gwinnett I'd say Gwinnett goes to Obama first. It's more diverse and its white population is declining at a faster rate.
I'm definitely thinking Obama could pick up a few more points in the "Black Belt", particularly in some of the counties that have strayed in recent years. Romney's going to have perhaps the lowest amount of support there in all of GA. There could also be some gains in the rural corridor between Athens and Augusta (McDuffie, Elbert, Wilkes) as well as in between Columbus and Atlanta (a la Meriwether).
I still think Cobb will flip before Gwinnett based solely on entropy; Gwinnett surged in 2008 and it's growing much faster, but it was a exceptionably huge surge (even for the changing demographics) and I don't think it will necessarily hold or keep up in pace. Cobb saw its margin shrink by 14 points in 2008, while Gwinnett had a major, 22 point margin reduction. On top of that, suburban whites typically are more moderate/progressive on the NW edge of Atlanta than in the NE section and I could see a lot of whites that supported Obama in 2008 defecting back in 2012. That could happen in Cobb, too. Who knows.
If the Latino population in Norcross (20% of Gwinnett County's pop) decides to start voting, in conjunction with the 10% Asian population and 24% AA population, then we can call Gwinnett before Cobb. Otherwise, I think the more moderate sections (i.e.: Kennesaw/KSU area) will carry Cobb to the D side first. It's quite possible that neither will happen this election cycle, though, and I do admit at being a little optimistic with flipping Cobb to the Democrats.
Gwinnett County whites are very conservative in the majority of the county. I think they will be mobilized enough to remove Obama that Romney's blandness won't have much effect. Then again, it's early days; he might yet make some major gaffes.
