Are you perhaps thinking of Ian Bicking's "Topics of Interest" talk [0] from PyCon 2009? It definitely veered into the uncomfortable, but there was some reasonable handling of the situation during the talk, IIRC, and was definitely a catalyst in the PSF adopting a formal diversity statement [1] and trying to be encourage inclusivity in the community.

[0]: http://us.pycon.org/2009/conference/schedule/event/76/

[1]: http://www.python.org/community/diversity/