I just came across this site that reviews lots of notebooks and measures illumination distribution. What become clear is that although we wish for better displays, Apple macbooks and macbook pros do fairly well compared to many other manufacturers, including Sony laptops. It's interesting to read some of reviews to compare.
http://www.notebookcheck.net/Reviews.55.0.html
http://www.notebookcheck.net/Review-Apple-MacBook-Pro.732.0.html
http://www.notebookcheck.net/Reviews.55.0.html
http://www.notebookcheck.net/Review-Apple-MacBook-Pro.732.0.html