Part of the problem is the various "chief's" associations seem to come out against it. You can bet, if the city's mayor is a member of the Mayor's against (illegal?) guns organization, the chief will be anti-carry.
What I find, anecdotally, from reading various stories from both liberal and conservative leaning sites, is that most big city departments, either via their senior brass or spokesperson, come out against it, while more rural departments come out for it. By "big" city, I'm talking about NYC/Chicago/LA-size cities (I realize those are all liberal cities, but you get the idea). There are, of course, smaller "big" cities that will come out against. Considering the violence level, I wouldn't be surprised if Atlanta PD is publicly against, though that's certainly not a popular opinion in Georgia; statistically, Atlanta is the only major "liberal" cluster though, which is not surprising considering our ghetto is probably larger than any other whole city in the state...
This would definitely be an interesting topic to bring up to the various state carry organizations, Georgia Carry, Florida Carry, etc, to see if they have/would do a survey of various departments around the state.