Illustrator CS3, about 9 hours.
And here's a close-up to see some of the detail (click the image to enlarge):
I modified my colouring method a little for this image. The line work is in different colours and I feathered some of the shine to make it more subtle. I also rendered her eyes a little differently, using lines to add some detail without getting too cartoony. The only black in this image is her pupils, and I think that really helps the image feel more soft and elegant.
Desktop wallpapers of this special available on request. I hope you enjoy the image.