Why Stop There?
"...we should prepare for a wave of HR consultants pointing to this study and looking for automated tools designed to analyse every aspect of a person’s online identity in order to figure out whether they have what it takes to man the drive-up window next summer."
But why end with the mere initial decision to employ? You could set up to get notifications of any change to an employee's Facebook profile (full access required, or you can't work for us!), reanalyze in real time, and if the employee no longer measures up, send an automatic termination notice. So much more "efficient" than those labor-intensive performance reviews.