I am re-posting from this thread:
My issue is more with the green hue in the top center/right. When I am reading, it reminds me of the after image effect you get from looking at a bright light, and then looking at a white page. In fact at first, that's what I thought it was. I even turned my Kindle upside down, to see if I still noticed the green area or if maybe it was an effect of how and where I was looking on the page. Turning the Kindle upside down the blob was still noticeable, just at the bottom of the screen.
I chatted with Kindle support, and offered to email them the pictures of my screen. The representative said that would be helpful. After receiving my pictures (and going through the standard factory reset, verifying that I hadn't dropped it or gotten it wet) they said rather then me exchanging it at Best Buy they would send out a new one. I have 30 days to return the defective one, or they will charge my credit card for the second unit. I was happy that I didn't have to send mine back first. My new one should be here by the 23rd, so I am keeping my fingers crossed.