Maybe it's a fact I'm not sure but I kinda figured it out just through observation.
Did you know that you can go to your profile on here and see which number your account was that signed up, chronologically?
For example, the URL for my page is mlpforums.com/user/6322-space-woona/
The 6322 in the URL tells me that I was the 6,322nd member to sign up for the forums.
Obviously, the number in Feld0's URL will be 1 as he created this place. Naturally, his account would be the first.
My number being only 6322 and there now being more than 20,000 members kinda says something as to how old my account is. That there were only 6,321 other members here when I signed up I guess you could say I'm one of the older members
I noticed this. It seemed like this number appeared in every profile URL and that it was smaller for older members and larger for newer members. So just by putting 2 and 2 together, I figured that it tells you which member you were to sign up.