At one of the evening events during OSCON 2011, a woman wearing one of her company's t-shirts was hailed by a man asking why he would want to use her company's product. During the ensuing discussion, he was somewhat belligerent, but she felt compelled to represent her company and so did not leave the conversation. Finally, he made a comment, she made a retort, and he hit her on the buttocks very hard, such that it was still stinging 10 minutes later. She said that this was not ok, and in response he announced he was going out for a smoke.
In light of the recent publicity regarding the treatment of women at conferences this incident was reported to O'Reilly and action is being taken.