With all that data and most users being logged into Facebook on their browser at all times, I cannot for the life of me figure out why they haven't released an Adsense competitor -

I'm assuming there are some deep philosophical reasons about not wanting to encourage any business decision that focuses entirely outside of the Facebook ecosystem, but hot damn, I would drop Adsense on my sites in a heartbeat for a FB version as I'm 100% convinced their service would easily defeat the competition in an ad relevancy test.

I can't imagine it's privacy related, because that's proven to mostly be only a minor hurdle to overcome every time everyone freaks out at every FB change.