Amanda Holden, one of the judges on "Britain's Got Talent", who has followed Boyle since she first appeared on that show and surprised everyone with her voice, called her U.S. TV debut "brilliant" on "The Early Show" Thursday.
"I thought it was the most self-assured, confident performance I've ever seen her do, and I think that it's really showing now in her personality," Holden said. "... It was beautiful, really beautiful. It blew me away."
"Early Show" co-anchor Julie Chen remarked that she didn't sound like Mick Jagger, the lead singer of the Rolling Stones.
Holden said she sounded better than Jagger. She added that she'd heard the song performed by Boyle two weeks before at fellow judge Simon Cowell's home.
"He put (her) CD on, and we listened and her voice just rang out into the darkness, and it was the most ethereal kind of spiritual moment ever. We all -- I thought even Simon was going to cry. He couldn't believe it."
Holden said Boyle sounds like a cross between Kate Bush and Barbra Streisand.
"Her voice quality is stunning," she said.
But what about Boyle's upgraded look? Has she gotten too glamorous?
Holden said Boyle's found the middle ground. "Last night I thought that's kind of good. That's a great look for her. It's the middle ground. The hair looks lovely, she doesn't have too much makeup on. She's got a very pretty face, and I think the makeup she had on last night kind of just accentuated that in a very subtle kind of way. …She was also kind of regal. I liked how she thanked the orchestra afterwards. She was very centered, very calm."
Watch the performance here and then register your opinion below the video box.