A little more work, and you can figure out who owns which address, because participants are paid according to the number of posts they make, which is already public information.
It wouldn't be public information without a spreadsheet. 
Yes, a determined adversary could certainly mimic DarkStar_'s job for several months and start to figure out who is who, but there is a big difference between that and a spreadsheet linking names and addresses. Just like someone could follow you for two weeks to learn your daily routine and when the best time would be to break in to your house, but there is a big difference between that and sticking a note on your door saying "I'm going to be at work for the next 12 hours".
And of course once people start changing their addresses, then the whole process becomes more difficult and less accurate.