Facebook advertising isn't keyword driven, it's interest driven. AFAIK Facebook doesn't parse your status updates to find keywords -- they look at what you have Liked.
They certainly do look for keywords in statuses (though I don't know if they use them for advertising). At one point they grouped statuses by subject ("Alice and Bob both mentioned Christmas"), and it suggests groups/pages based on your statuses (I mentioned reading something in French in a status, and it suggested I liked "French language").
Yeah I was referring to advertising purposes. Even if they did use keywords in statuses for advertising I would imagine the the weight of those keywords verses the weight of a liked object would be significantly lower since the relevancy would be low.
