And people still keep putting their serial numbers with their posts...
Again, serial number doesn't mean anything with regard to screen color!
You take 10 people with a "C39" and 4 will have yellow, 3 will have blue, and 3 will be in between. There is no correlation.
That being said, for all of those with yellow screens, instead of complaining about it here, why not go to the apple store, compare with floor models and see if you can get it swapped for a better one?