Smart Advertising on Facebook

So, I'm on facebook. I didn't put much into creating my profile. About a month ago on a whim I put dwarf fortress up as  my one and only activity. I also put it up as my one and only interest. Sadly, there was a week in there when both could have been true. Anyway, facebook uses smart advertising kind of like the google search engine. Instead of  advertisements popping up in connection with your search criteria I guess facebook's system uses whatever you decide to put in your profile because I started getting some weird ads.

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