Fake user identification

You know it occurs that in this age of social profiles and freely available public records it oughta be possible to automatically identify fake users with a fairly high degree of accuracy. Seems like it could go a long way to catching people who are scamming user reviews. Although, it probably wouldn’t do anything about the “reviews for purchase” problem in which people are paid to use their real identity to do reviews. Seems like community policing is probably still the best bet there.