The great thing about social media is that developers such as Infinity Ward are able to tweet about developments in Modern Warfare 3 Elite; in this case, the tweet says that on the 16th August players can expect to receive 16, 17 and 18 content drops!
According to the official Infinity Ward Twitter a tweet states;
Next #MW3 PS3 Elite content drops 8/16. Includes: 2 MP maps Decommission & Offshore + Spec Ops mission Vertigo (shown). pic.twitter.com/MZXt13ce