I first read this about a year ago, a very detailed hoax IMO.
The first thought I couldnt shake when reading this is the old question "If you could go back in time, what would you do?" and not once could I think of any concievable reason to go back in time to post on a forum
Looks to me like either the guy who done this was very bored or it could have been part of a psychological experiment. I heard about somone who done something like this for a psycology thesis (Or something similar), basicly its a study of peoples reactions.