The dataset comes with GPS locations of users and venues. With that data alone you can retrieve individual addresses in not too densely populated areas. Missing links will get caught in the social net.

We already learned that Warhol's 15 minutes of fame should read 15 megabytes , but, to cut the "it's the users choice to post that data" apologists short: almost no-one I speak to understands the implications of all possible interpretations, classifications and groupings that their online traces allow.