Re: @Loyal Commenter
You WHAAAAT? That screen must be either massive or your nose must be touching it, either way you must have really poor vision to only be able to make out a pixel if you squint. I think a trip to the opticians is in order for you (and get them to check you for tunnel vision first).
OK, let me clarify for those who don't know how human eyes work.
The full field of vision subtends about 130 degrees horizontally. However, the only part where you can see anything in any amount of detail is the central 10 - 15 degrees, and you can only see detail in the central 2 degrees, which is where the image falls on the fovea. Everything else is essentially peripheral vision, where you only see basic shapes, colours and movement. This is why your eyeballs can move around to point at things, in order to see them.
FYI, I work with a 20" monitor, located around 18 inches in front of me. This fills my functional field of vision. Obviously, I can still see things in my peripheral vision, but if these were on a screen, I wouldn't be able to tell whether they were in high definition, or a single coloured pixel. This is quite normal.
At this distance, I can just make out if a dark spot on a white background is one pixel, or two; note that I am talking about visual acuity here, not whether I can see the pixel or not. I am one of the lucky 5% or so of people who don't need glasses, and can quite happily read notices on the wall at the other end of the room that others who wear glasses cannot. I think I'll put off that trip to the opticians for a little while yet thank you.
Anyway, my point stands that there is little point in an ultra-HD television. At a distance where the whole image comfortably falls into your field of vision (several metres, depending on the size of your set), you won't be able to make out the pixel-level of detail, particularly since the image will be constantly moving and changing. IMHO, they are nothing more than status symbols, like personalised registration plates, or monogrammed golf clubs. If you have the cash spare to buy one, consider doing something philanthropic with it instead.