I'm pretty sure the IDs aren't generated sequentially. Sometime in the last year or so, they started prepending '100000' onto each new user ID. Also, the rest o

I'm pretty sure the IDs aren't generated sequentially. Sometime in the last year or so, they started prepending '100000' onto each new user ID. Also, the rest of the new ID format is at least 11 digits long. I'm not sure how they did it in 2004, though.