So, I was in the audience for this. And it pretty much happened exactly as the article describes. Mukasey was giving his speech, and seemed like he was winding it up, when all of a sudden he started slurring. Then a few seconds later he was kind of stuttering the same word over and over, like a broken record, and then he started to tip forward. At this point only a few seconds had gone by really, but it was pretty clear to the audience what was going on. So a few people ran up to help him, and I have to say, I've never seen a more respectful audience of hundreds of people. Everyone stayed in their seats, they turned the lights down low, and people were virtually silent for at least twenty minutes, while they were helping him, and then the paramedics came and took him away. It was kind of amazing how long it took the paramedics to get there, actually. So the entire room just sat there in silence, watching and waiting. They finally took him away, and then the emcee got back on the mike and said a prayer, and then told everyone that the evening was over. This was a lawyers' Federalist Society convention, so when it first happened somebody got up and was shouting "Is there a doctor in the house?" Which was weird in and of itself because I thought they only said that in the movies. So the guy said it like twice, and then after getting no response, kind of muttered under his breath "bunch of lawyers." I thought that was kind of amusing.
The article just says that he collapsed, but it looked like a stroke to my very uneducated eyes. And I know other people in the audience said the same thing.