If you think of advertising as "traditional advertising" and "internet advertising", then FB and Google are certainly rivals. However, in pure marketing terms, they are actually very different.
Google search ads EXCEL in "Demand Fulfillment" - say you want need a plumber now since your toilet is overflowing. I don't think Facebook will ever beat Google here. Google sort of created this niche where they were better than any competitor that had ever existed.
Facebook, on the other hand, is better at demand generation. Consider advertisers who want to reach teenagers who would want to buy videogames - a new game is coming out, and they want you to know about it. Before, you'd have to find the TV shows that they would watch, or billboards that they would see, or queries that gaming-teens would search for, and advertise there. These are all competitive and difficult proxies for the audience you want to reach. Facebook is a much better place for that than Google.
In fact, you can imagine synergy between FB ads and Google ads. FB tells people, "you should listen to this band that you haven't heard of", and when you Google that band name, you see ads for places to buy tickets and albums.
Google has AdSense / Doubclick network. This is a huge number of eyeballs with many banner types. And Google knows my basic browsing history via cookies and my entire search history. At least for me, Google knows exactly what I'm interested in, tend to purchase, and tend to click on. Facebook knows my basic demographic profile, which isn't really that valuable. I'd say the value of Google's data is about 50 times Facebooks.
Agree completely, in fact I sort said some of these things at another message on this thread. An like I said in the parent, Google vs. FB is not a fight that I particular believe, but I was hoping to shed some light on why people make this connection.
Google has money in abundance, they're putting millions on social projects, hoping to have some of FB's thunder (and data). While I don't know if Google will ever succeed, every social feature added by Google is a point of conflict with FB, thus feeding the "there's a war going on" opinion of some people.
I'm not sure your plumber example really works out. Facebook could hypothetically tell you that "Your friends X and Y used plumber's Z services, and liked it!", which is much more persuasive information than a generic ad.
Google search ads EXCEL in "Demand Fulfillment" - say you want need a plumber now since your toilet is overflowing. I don't think Facebook will ever beat Google here. Google sort of created this niche where they were better than any competitor that had ever existed.
Facebook, on the other hand, is better at demand generation. Consider advertisers who want to reach teenagers who would want to buy videogames - a new game is coming out, and they want you to know about it. Before, you'd have to find the TV shows that they would watch, or billboards that they would see, or queries that gaming-teens would search for, and advertise there. These are all competitive and difficult proxies for the audience you want to reach. Facebook is a much better place for that than Google.
In fact, you can imagine synergy between FB ads and Google ads. FB tells people, "you should listen to this band that you haven't heard of", and when you Google that band name, you see ads for places to buy tickets and albums.