Right now, the most impressive visuals seem to come from high frame rate, and good use of HDR. At least, that's what I find most impressive.
With that said, I do appreciate high resolution. It is an important factor. But, it isn't the only factor, though it sometimes seems like marketers think it is. I assume we got to this point because resolution is easy to explain, easy to understand, and easy to quantify. So, its the low hanging fruit for the marketing department.