So the following popped up in my mailbox:
It is nice and joyful to see your profile on https://github.com and i thought is beautiful to make you a friend,looking for a good friendship, mail me to my box, because i am not often here on firstname.lastname@example.org for more introduction and i will send you my picture.
I guess it was bound to happen. Anywhere you allow messaging to occur, spam will follow. I only wonder why it took so long to happen via a popular service like this.