Stroke of genius picking this old stones tune. It’s not a song I would have picked for her that’s for sure.
Fantastic arrangement and a moving performance.
Update.
Youtube video has been removed. 
Try this one instead courtesy of the Dailyrecord.co.uk.
doh! it has been removed from YouTube
The audio only preview is still available on the Times website.
http://entertainment.timesonline.co.uk/tol/arts_and_entertainment/music/article6834008.ece
Oh, found another source of the tv performance.
http://www.dailyrecord.co.uk/videos-pics/entertainment/videos/2009/09/17/susan-boyle-sings-on-america-s-got-talent-86908-21679435/
Will edit original post.