Thanks to Bobad for posting the link. I've been hearing about Susan Boyle's performance all week, and was curious to see it.

My son, who some of you have met, was on the American version of the show last year – part of a non-musical act. Some of the acts, like my son's, were invited to participate rather than coming in off the street. The acts went through a couple screening rounds before performing for the celebrity judges, so the producers knew exactly what they were before anything was recorded. I'd be surprised if the judges were told anything about the acts because part of the fun is seeing their reactions. Anyway, when the celeb judges finally showed up hours and hours of performance were recorded. All the participants signed non-disclosure agreement, were sworn to secrecy, and went home. Weeks went by while the hours and hours of recorded material was edited into storylines lasting a few minutes each. Then everyone jumped on a plane and went to Las Vegas for the finals. After a couple days of pointless milling around the producers sent a bunch of the acts home, including my son's. Apparently there were more acts put through to the finals than were actually needed to fill out the shows. The prizes on the Yank version were $1,000,000 cash and a chance to perform in a Las Vegas show.

I don't really know, but if the Brit version was produced like the Yank version then Ms Boyles' performance was recorded weeks ago.
- Phil