Old information, but found this:
"While G1GABLASTSM service availability continues to expand in its existing markets, the company said it also is actively deploying broadband network infrastructure in parts of Arkansas, Louisiana, Rhode Island, Oklahoma and Virginia to bring G1GABLASTSM to customers in those states. The service will launch in those areas starting later this summer. Cox's residential gigabit service will be available in all of its markets by the end of 2016." May 5, 2015
According to this, the infrastructure is already in place, just working out the kinks to actually allow it. The thing is, it will probably only be built into very new areas. The fiber should already be in place. If you haven't seen Cox trucks digging in your area, you probably won't have it.
As for a map, I doubt it. With Cox, saying less is more. They rarely release deployment schedules at all, and I have never once seen a map. They don't want to promise something and then not deliver. "Ask me no questions and I will tell you no lies".