Earlier quoted context omitted.
I loved listening to the Stack Overflow podcast with Jeff and Joel. It was kinda crazy that they were doing a podcast like that while they (Jeff mostly) were building it and coming up with the name, etc. Still have all the mp3's somewhere. Edit: I'm in the top 2%. Most of my rep. comes from interest earned on questions/answers I posted very early on.
Interesting. I'm also in the top 2%, but I'm far from being an early adopter on that site, with a userId in the hundreds of thousands: https://stackoverflow.com/users/343302/dotancohen I was never even very active. I can only suppose that only 1 out of every 50 signups ever accrues any real significant amount of rep.
But any such "interest" does apply to the magnitude of the initial contribution, so merely being around for long is not enough - you had to have a sufficiently productive period of activity to capitalize on.