You know, I have a rMBP and I'll be getting it back tomorrow from repairs (got my LG screen replaced with Samsung panel after burn-in emerged after a few months of use). This is my first issue with the computer and I haven't really had anything else go wrong with aside from the scrolling-lag that occurred early on but it got significantly better with OSX updates.
I'd say the display panel issue is a definite annoyance, but it's not as if it makes the computer unusable. Obviously, a $2000+ computer shouldn't have any kind of ghosting issues, but it was a first-gen product and hey, sometimes stuff like this just happens. I am surprised how poorly Apple has handled the entire scenario, however. Although I had no issues whatsoever in getting a replacement (he ran a standard burn-in diagnostic test with the checkerboard, it was obvious after 3-minute test), I know many others have and that's what not right. If any other major issues emerge after too much longer, Apple should honestly find a way to make things right, whether it be replacement machines or whatever. I don't know how they need to handle the issues, particularly as they'll grow in numbers as the panel gets older and burn-in becomes more noticable to users of the computer, but Apple definitely needs to address some of these issues users are having.
Overall, do I have a problem recommending the computer to my friends and family? Probably not. I still feel it's leaps and bounds in front of any other laptop on the market today. Unfortunately for me but fortunately for everyone that doesn't own a 2012 model, Apple made some significant tweaks in the 2013 model, and obviously there was something going on to make 4-5 semi-major design tweaks. That being said, Apple making changes in the time-frame they did represents why they are Apple and how they will always make a better product. And the products have a one year warranty, so I really don't think there's anything to worry about buying a 2013 model, especially.
If anything else goes wrong with my Retina, I'll probably see if I can get free Applecare or something along those lines. I don't think it'll be fair for the early adopters to live in fear after the warranty is up!