1 - fb has the potential to be the first serious adsense competitor: slightly poorer context data (though they certainly can repeat much of the work google has done, and I bet bing would love to do a data deal with them) but much better data about the user. Adsense earns roughly $10B/ year; ex my quick guess at tac (23% from 2009q4) and adsense makes $7.7B/year net. FB stands to take a bunch of that if they wish. They still are trying to invent new types of social advertising, and it would certainly be weird if facebook.com was just a giant data honeypot, but they have the data and the technical ability. And the demand from pubs is certainly there: pubs love anyone who pays them.

2 - anybody citing GM pulling $10M in annual spend is an idiot, unless you think GM is in the business of sending out press releases announcing all of their advertising budget changes. No? Then there's something else going on here; perhaps some bare-knuckled negotiation tactics.

3 - fb collects a tax on gaming. Plus Zynga and some others may be cleared to start doing online poker for real money [1]. fb taxes that at 30%.

4 - low ctr is fine for direct response as long as you have proportionally low costs. What this does for the user experience is another question =P

5 - lots of people in adtech very much want Google not to win everything. See the rise of the ABG (anybody but google) exchange: appnexus + aol + microsoft [2]. I expect yahoo inventory to start showing up there once yahoo realizes they no longer have the technical ability to run an ad exchange. Scott talking about selling off rmx can't have helped retain technical talent, and at this point it's a fat question why anyone would want it. Yahoo will sell a bunch of guaranteed delivery, but I think a bunch of the rest will show up on appnexus eventually, if it isn't already there blind.

5a - contributing to the above, hopefully google will get investigated for antitrust. For starters, hiding search query terms in the referrer string should trigger an investigation. They use that data in adsense, and it's particularly valuable for targeting ads on low text pages. Now they're hiding that from other ad networks, I can't find any public statement guaranteeing they're not letting adsense see it. Google also uses search query results to juice display retargeting.

6 - ctr isn't particularly important for brand advertisers. There is a growing disparity of the ratios of ad spend / time spent in different media, with TV higher. Thus behind some of fb's valuation is the thesis that brand advertising dollars will be moving from tv to online, and fb is probably poised to take a big chunk of those. If/when this happens is unknown, but winning bets on those sorts of things is how investors get paid.

7 - fb may still be given a giant present from the EU depending on just how their anti cookie laws work in practice. The morons in GB rolled it all back 24h before the implementation deadline, but other member states may go all in and more or less ban 3rd party cookies. Then we'll be stuck in a tagless world, and I bet fb will get an enormous amount of spend.

[1] http://venturebeat.com/2012/01/20/the-deanbeat-should-zynga-...

[2] http://www.adweek.com/news/technology/aol-make-inventory-ava...