Not much to read on the original article but the article is here [1]
According to itnews.it...
Paul Potts made #10 on the top 10 best genuine smiles.
Below is the list (bit confusing, but they listed best & worst side by side)
Top 10 best genuine smiles Top 10 worst fake smiles 1. Julia Roberts (47%) 1. Victoria Beckham (38%) 2. Simon Cowell (25%) 2. George Bush (26%) 3. Ugly Betty (21%) 3. Britney Spears (17%) 4. Mona Lisa (5%) 4. Tony Blair (14%) 5. George Clooney (2%) 5. Diana Ross (5%) 6. Cameron Diaz 6. Gordon Brown 7. David Beckham 7. Jennifer Aniston 8. Jessica Simpson 8. Madonna 9. Beyonce Knowles 9. Paris Hilton 10. Paul Potts 10. Prince Charles
Links:
[1] http://www.itnews.it/news/2008/0902120201499/the-art-of-speaking-without-saying-a-word-what-s-in-a-smile.html
[2] http://www.paulpottsfanclub.com/hm-no-christmas-cd-paul-potts-year
[3] http://www.paulpottsfanclub.com/donnie-new-kids-on-the-block