When notebookcheck.com reviewed the 17" MBP they confirmed what my pictures show. They divided the display into 9 sections and measured each section's brightness. This clearly shows the objective differences between the left one-third and the rest of the display. Quite horrific that Apple would allow such variation in brightness.
http://www.notebookcheck.net/Review-Apple-MacBook-Pro-17-inch.1298.0.html
Upper row, starting from left
Left 180.6 cd/m²
Middle 218.7cd/m²
right 207.2cd/m²
Middle row, starting from left:
left176.3cd/m²
middle226.5cd/m²
right217.4cd/m²
Lower row, starting from left
left183.7cd/m²
middle211.5cd/m²
right218.5cd/m²
http://www.notebookcheck.net/Review-Apple-MacBook-Pro-17-inch.1298.0.html
Upper row, starting from left
Left 180.6 cd/m²
Middle 218.7cd/m²
right 207.2cd/m²
Middle row, starting from left:
left176.3cd/m²
middle226.5cd/m²
right217.4cd/m²
Lower row, starting from left
left183.7cd/m²
middle211.5cd/m²
right218.5cd/m²