I have a friend who related personally witnessing a negligent discharge at his church just this past Sunday. He said he was sitting in the church (either just before or during services...I forget), when he heard a very loud "bang." He said a man got up and walked out, and then he heard someone yell "call 911." He said some initially thought it was a drive-by, but it turns out that the man in question had a pistol in his waistband, which had apparently fired when he bent over. My friend said he went to where the man had been sitting, and there was a hole in the seat and in the floor. Police responded and took a report while the man was taken for medical attention.
My friend said he didn't think it was in a holster, which was my first guess as to the cause (the "Plaxico Burress carry"). The man was injured, in a life-changing if not life threatening way...he was apparently using a half-assed appendix carry (sans holster)...and shot off the end of his "equipment."
I have not been able to find any news coverage