I'm still having video card errors on my RMBP where the whole machine locks up. Finally called Apple, I'm just going to bring it into the store tomorrow. Sick of these freezing issues.
I've had major issues with the graphics card and system locking up, too (but very intermittently, impossible to reproduce on-demand). I sent it to Apple, they had it for 10 days and returned it saying nothing was wrong... but finally agreed to just take it back and refund my money. (I'd been without it for a month after the SSD died and it took Apple about 10 days to get that back to me... then the video issues cropped up.)
This was the 2nd of 3 Retinas I bought on day one of their release that has had graphics issues.