I agree completely. Let's say I'm an advertiser. I can put my ads next to a wall of search results, on some random blogs, etc... OR I can put my ads next to the photos, videos and profiles of the target customer's friends and relatives. Facebook allows an advertisers to tap directly into potential customer's lives, associating themselves directly.

Plus, fb has nearly perfect demographic information. If I want to advertise ONLY to divorced single moms, ages 35-45 in Cleveland who have birthdays in December, and identify as republican, I've got all that info right there on fb. Google can only guess.

Good point. Because of the user profile, FB can say with greater certainty that an ad was clicked on by a real person.