Well, that was a surprise for me - seeing Little Voice on TV tonight, as I wasn't expecting it. Still, I'm glad that I watched it as now I have a better idea of the storyline - so I know what people are talking about when they have been to see the play. I was amazed to see Obi-Wan Kenobi playing the part of Billy - I wasn't expecting that!
I can see how (in my opinion) Diana would make a better character for LV than Jane Horrocks - partly because she is younger and so more believable in that sense - but also because I think her voice is better (although I am biased

) . I could only compare their voices by what little clips I have heard of Diana on the web, and I definitely thought that for the song "Get Happy", Diana's voice was by far and away more rounded. Perhaps it's not good to compare them though - as they are different people, each bringing their own talents to the role.
I wonder if Diana watched this tonight?