I don't know if OMGPOP integrated with Open Graph, but there story is certainly similar.
A mobile app powered largely by Facebook interactions takes off like a rocket ship. In less than month is adds so many millions of users that it gets bought for $180 million dollars.
A company that was in the red is suddenly worth a ton of cash. Cut to a few weeks later, and Draw Something is shedding users like water off a duck's back.
http://www.betabeat.com/2012/05/02/draw-something-decline-om...