Yes, you get to use the Delta lounges in Atlanta.
http://www.airfrance.sg/SG/en/common..._airfrance.htm
How to access Air France airport lounges
To take advantage of one of the 530 Air France and SkyTeam airport lounges, you must travel on an AIR FRANCE, KLM, or SkyTeam flight and be a:
* La Première or Affaires passenger with Air France,
* Business class passenger on a SkyTeam international flight,
* Flying Blue Gold, Platinum, or SkyTeam Elite Plus member.