Not a play area but my wife and our then 7 month old son were admitted to the Delta Crown Club in ATL (and once in SLC) to wait out a 2-hour layover that turned into 3-1/2 hours. She said it was a big help being away from the hustle and bustle because she could rest and the baby took a longer than usual nap. Had they been in the terminal area, he would have been flirting with every lady walking by