http://social.expression.microsoft.com/Forums/en-US/design/thread/2c564262-27c9-4065-9812-04ccccef6a57here in this thread are different methods how to get transparancy
if you save the image
jpg extension doesnt support transparancy(as far as I know) you will have to save your image in
png
and here Annie s tutorial
http://blogs.msdn.com/expression/pages/removing-backgrounds-from-photos.aspxgreetings