Facebook does not take a cut of third-party display advertising.
For example, if an advertiser pays Zynga to put a banner ad in their application or above the Flash widget containing their game, Facebook doesn't see a penny of that.
Zynga pays Facebook to advertiser in the right-hand column, though. Lots.
Additionally (and this doesn't count towards advertising revenue), Facebook Credits are mandatory for all games on the Facebook Platform, and Facebook takes a 30% cut any time a player purchases some.
For example, if an advertiser pays Zynga to put a banner ad in their application or above the Flash widget containing their game, Facebook doesn't see a penny of that.
Zynga pays Facebook to advertiser in the right-hand column, though. Lots.
Additionally (and this doesn't count towards advertising revenue), Facebook Credits are mandatory for all games on the Facebook Platform, and Facebook takes a 30% cut any time a player purchases some.