I've been in contact with an attendee at tonight's Federalist Society meeting where Attorney General Mukasey spoke for roughly twenty minutes before collapsing
According to this trusted eyewitness, events transpired roughly as follows.
Attorney General Mukasey was roughly twenty minutes into a speech defending the administration's torture policies and particularly arguing against prosecutions of people who made decisions in the aftermath of 9/11 (essentially arguing against what he believed amounted to the criminalization of policy differences).
Some seven or eight minutes prior to the incident a heckler start shouting, calling Mukasey a "tyrant." But the AG seemed unfazed by this; and members of the audience shouted the heckler down.
The eyewitness tells me that Mukasey seemed particularly in earnest about the argument he was making. And when he first began to falter it appeared he was merely choking up. Soon, what at first appeared to be choking up blended into slurred words. Twenty to thirty seconds later he collapsed, his fall broken by a nearby FBI agent.
The room fell silent. After a moment there were shouts from the table where Mukasey's wife was sitting, calling to turn down the stage lights. A woman in an evening gown, presumably a doctor, ran up to the stage and the FBI agents hovering over Mukasey allowed her to attend to him.
The eyewitness told me that Mukasey collapsed at approximinately 10:06 and was taken off on a stretcher at approximately 10:33.
The one additional detail is that this eyewitness says that the medical personnel attending to Mukasey were talking to him for at least part of that period, at one point asking him "can you wiggle your toes." In other words, it appears that Mukasey did regain consciousness to at least some degree before being taken to the hospital.
As emergency personnel were attending to Mukasey, a group of Republican luminaries, including former Attorney General Ashcroft and his wife, created a cordon between Mukasey and the audience to create some degree of privacy.
After Mukasey was taken away the audience was led in a prayer for Mukasey by former Congressman David McIntosh (R-IN).