I think you have left out the brand advertising, advertising that needs to hit the customer much before he is looking for something and do so repeatedly. That is the segment where Facebook seems to have a clear edge.
Google can get into action when the intention finally surfaces in form of a search. Facebook can help you to create the association between a brand and that intent in the stage before that manifestation. For example, when you are thinking of buying a smart phone, you will search for the "cheap smart phone" and restrict yourself to 4-5 top brands in your head. Or how when looking for "cheap flights", I have preference for certain airlines. Brand Advertising can help you get into that top group in people's head.
If that pie of the advertising is big enough, I have no idea.
Google can get into action when the intention finally surfaces in form of a search. Facebook can help you to create the association between a brand and that intent in the stage before that manifestation. For example, when you are thinking of buying a smart phone, you will search for the "cheap smart phone" and restrict yourself to 4-5 top brands in your head. Or how when looking for "cheap flights", I have preference for certain airlines. Brand Advertising can help you get into that top group in people's head.
If that pie of the advertising is big enough, I have no idea.