At least one app (it may have been more) was able to harvest data about those using the app as well as their FB connections. So FB didn't "hand the data over" but weaknesses in FB's technical infrastructure were exploited to pull across data, which was then subsequently manipulated.
Nearly 7% taken off the Facebook share price yesterday as a result of this story.
Could be a buying opportunity if you were looking to get in.
#EveryCloud