While the growth in ad sales may not surprise marketers, what is surprising is the segment attributing to much of that growth - Facebook's self-serve ad platform, which caters to local advertisers who have gotten away from the old tried and true yellow pages listings. eMarketer estimates that self-serve ads represent around half of Facebook's ad revenues. The other half is from display advertising.
I would expect to see ad spending increase on Facebook for the next couple of years as more companies - especially retail begin to focus more of their media spend on social networks as opposed to television networks and some of the more traditional media. Gap's fall campaign last year is a great example of this shift from traditional channels to social media channels (Facebook and YouTube).
