That would be easy enough to test, feed it a 2160p static image with alternating black/white horizontal lines and check with a magnifying glass (turn all 'enhancement' modes off first).
However if this TV was only capable of 720p images, I suspect the people in this thread might just have noticed by now...
Andre
This is the best 3D TV ever, in my view, alongside higher end models from the same year. I found active solutions (with powered glasses) much harder in the eyes. Not really concerned about the actual resolution, as the 3D image is incredible. Dreading the day my E6 dies, as, while I'll doubtless see an upgrade in other areas of core performance with a current OLED, it will be no compensation whatsoever for loosing 3D.