[talentdeficit]

for the most part, facebook can only target you when you're on facebook. google now targets you across their properties some of which have significant lock in. it's not as easy to escape google being creepy as it is to escape facebook being creepy.

[cromwellian]

Facebook can target you across any site that has a Facebook Connect or Like button, and eventually they will turn those Like Buttons and Comment plugins into display ads.

[talmand]

I would say Facebook is far worse because they have easy access to more data about you that you more than likely provided. Then there's the data that they get about you from your friends. And as pointed out, Facebook has been tracking people outside of Facebook on any page that had their like button code in place.