I have a 2.6/16GB RAM have used it for 6-7 weeks and the ghosting just started today.
Mine was the same way. It was the LG screen, I bought it on day one, and it was fine until a couple of days ago. The ghosting just started happening out of the blue, and BAD.
I talked to Apple support yesterday, and they made me an appointment for today for a swap. I was also told, they wanted my machine for the engineers to test. My new model is the Samsung screen, and I'm happy so far!
Something else to consider... Unless this was happening from day one, they MAY opt to repair and not swap out. My Apple support guy on the phone more or less talked me into saying I had issues out of the box. Just something to consider when you decide how you're going to move on it.