Well, I was waiting for ESR to announce it, but the OSI has finally launched a 'certification' mark. It was on /. today, so I guess its a free for all now.
I like to call it the "Am I open source or not?" logo.
That's what my 'dusting of your T-shirt making machine' comment was about previously in my diary here on advogato.
Colin Viebrock is the graphic designer & Rasmus collected them all back when the board started soliciting entries.