I love the singing of Eva Cassidy who could perform wonderful interpretations of jazz, blues, folk, gospel, country and pop classics without any problems (sometimes cringe making) of 'crossover'
It was probably this inability to be put into any single recording genre and her reluctance to limit herself to any single style that hindered the important recording deal

enjoy and thanks for the memory jeff a 'thread drift' well worth it

Personally, I think Susan Boyle should stick to what she obviously does best, there is a large enough audience for that style of singing and a wealth of material to deaw upon.