Let's call in CSI-FResno.
It looks like a LOT of assumptions are being made in this article, such as assuming member number systems have been consistantly used the same way, assuming consistant rate of failed sign up, assuming a rate of failed sign ups as the basis, and so on.. Sounds like someone with too much time on their hands and a weird obsession.
LOL, I just noticed, "'The 100,000th Freeper" is just a member name, not a number. Who knows what sign up number they had. I can go create an account now titled the "Billionth Freeper" and it no way means we have a billion freepers.