Guest contribution from Randy Rothenberg of the IAB

Randy posted this excellent and as always insightful comment on my Facebook piece. Thanks so much!

I herewith support Rob's blog -- in word and deed! I want to throw in some wild cards, though. The analysis assumes all viewership of Facebook ads will be by Facebook members on Facebook. But two phenomena could upend this: syndication (the intentional placement of content, including advertising, in multiple venues); and "decontextualization" (the extraction of content from its primary venue into multiple venues). Syndication is primarily associated these days with networks, while decontextualization is associated with widgets.In other words, Facebook content (ads included) won't only be seen on Facebook (and the same with other content-hosting sites). If you accept that premise, you also have to accept a corollary: there will be different pricing schemes, based on context. On average, Rob's math may still work out -- although I'd be very cautious about extrapolating from today's CPM's to future pricing schemes, especially as consumers become habituated to some sites and those sites, in turn, are able to charge increasing environmental premiums.