I bought my Macbook Pro with Retina Display on July 7 at an Apple Store. It's the first Mac computer I have ever owned, and I am very, very pleased with it. I heard about the burn-in issue weeks ago, while my computer was still within the 14 day return period. I tried to reproduce it by leaving a bright window up on half of my desktop for about 10 minutes and then switching to a neutral color (grey) background and looking for a ghost image. I was relieved to not see anything and thought my laptop didn't have the problem.
However, last night I left a Finder window open for 10 or 15 minutes and when I switched to a virtualbox screen running Windows 7 with Windows 7's default desktop color, sort of a light bluish-grey, I was surprised to see the faint shadow of the Finder window still present.
So it looks like my rMBP has the problem as well. I don't know if it's something that developed over time, or if the specific actions for reproducing it using a bluish background instead of grey has made it suddenly more obvious even though the problem may have been there all along.
In any case, I'm not sure what I'm going to do about it. For me, it's not a huge problem; in fact, it seems like a fairly insignificant issue for the type of work that I do. If I were a graphic designer or photographer or something like that, the visual fidelity of my display would be much more important; but as a programmer, I mostly couldn't care less if there is slight ghosting here and there.
On the other hand, I did pay a great deal of money for this laptop, and I feel like it should function without this type of flaw.
I don't have it with me right now, but when I do, I will follow the instructions in this discussion on how to identify the manufacturing date and panel type. I am sure that when I read more detail in this discussion I will know what to expect for my options for solving this problem; I only hope that whatever the solution is, retains the contents of my hard drive, as I don't want to have to go through the hassle of setting up everything the way I like it again.
To follow on with a question:
If this problem is not terribly important to me at the moment, is there any risk in waiting a few months before acting on it? The discussions thus far suggest to me that this issue may be resolved on later versions of the screen, maybe they are making adjustments to the manufacturing process as we speak and in 4 - 6 months all screens will be burn-in free. Given this, is there any risk in waiting to report the issue to Apple? I didn't buy the extended AppleCare warranty, but I believe that the default warranty is for 1 year. If I wait 6 months before acting on this, can Apple refuse to do anything about it because I've used the screen for that long?