Interview with her voice teacher, the Independent does not allow a link to the article,

so just Google:

The Independent Don't Lose the tune, warns man who taught Susan Boyle to sing


-- snip

But he has reservations about the TV talent show route to fame: "Sometimes I feel it is so sensationalist. I feel they sometimes are not allowing the more intelligent Susan to come forward. I look at the names people are calling her and I think this is worse than what she is leaving behind. This is not respecting someone, saying they have a voice like an angel and then calling them names," he said.

"Susan is a woman you can sit down with and have a very intelligent conversation. She is one person with whom I can say about my own act 'do you think that song should be dropped?' or 'is that working?' She is one person whose judgement you can really trust."

He said the much-reported mild brain damage she sustained during birth barely affected her daily life.

"She is being portrayed as being lucky but she is someone who is not just a talented woman but she has a real intelligence. She may have had the problem when she was born but it does not affect her 99 per cent of the time.

--snip