Instead of starting a new thread on this subject, I thought I'd ask here to conserve bandwidth!
May I ask other D300 owners do a test to see if this issue is more prevalant than it appears to be since there have only been a few replies to the OP's question in this thread ....
Take off the plastic protective screen. Make sure the LCD glass is as clean as you can get it.
Take the camera outside during afternoon hours when there are only a few, if any, clouds in the sky.
Keeping the LCD turned off, look at the LCD while tilting the camera through various angles and see if you see faint streaks/smears under the glass panel. (Between the LCD and glass)
I have a feeling that there are more cameras out there with this issue than people think.
The reason I ask is this: I really don't want to send my camera in for repair on something that doesn't affect image quality. I can live with the issue, and knowing other's are out there living with the same issue simply helps me remain comfortable with my decision to NOT send in the camera for something that is 'normal'!
It's slightly annoying, but not enough to live without the camera for any length of time...