I'm 17722 and also felt late. I was a holdout on Subversion and was resistant to Git in general since SVN still worked fine and had good tooling, but eventually some client work moved to Git and thus eventually Github.
We must have joined around the same time, 17498. Funny to call us late when this would have been July 2008, or ~3 months after public launch.
I'm ~46,0000 and I thought I was early!
I'm around 1M and I have a three-character username, which also feels like I was early
I was too loyal to mercurial, only switched to git/github long after the battle was lost and won.
Hah! I was too. I was at a bar with Chris trying to convince him to base the company off of hg instead of git but they already had the domain name and had already started building it.