URL Relations with ampersands in the URL aren't being escaped in XML returned by the WebService API.
Which is the artist information for George Formby:
What has this URL associated with him:
This is causing 500 errors on the BBC Music site:
Music - John Coltrane: http://www.bbc.co.uk/music/artists/b625448e-bf4a-41c3-a421-72ad46cdb831
Music - Charlie Parker: http://www.bbc.co.uk/music/artists/c7356af9-9ea6-4a78-a55b-c73775716312
Music - George Formby: http://www.bbc.co.uk/music/artists/f5d51e0f-323e-46de-96ce-d427fd4b124c