Susan Boyle, YouTube Sensation, Sings For America (VIDEO)

Susan Boyle, the British talent show competitor who became a YouTube sensation this week, made her first US appearance Thursday morning.

She told CBS's "The Early Show that her fame 'hasn't really sunk in yet.' and that her performance was for her mother, who died recently.

"I wanted to make this a tribute to my mother," Boyle said. "I knew it was something I had to do. I had to get on with it. That's where the courage came from, my mother."

She then sang a bit for the hosts, and nailed every note.

WATCH THE WHOLE SEGMENT (singing at 3:55):