my living room is barely large enough for a 42"...
I'd imagine that the new TV's won't all be that big (100") but rather be "normal" sized and allow for more dots per inch, which allows less pixelation (it would be zero for the reason you stated, that the eye can't go much more complex than what we already get from 1080) and the images will look more "analogue" rather than "digital".
then the detail will never again be added through additional pixels. that "age" will be over. the possible way to give more detail would then be to increase complexity of 3D objects in our games and higher resolution textures on those objects.
A good GT example is that when you zoom in on the dirt textures, you can see blockiness. That will soon be a thing of the past, where all textures could be as complex as the dots on your tv... one to one. Imagine taking a high res photo of the sand on a beach. Now imagine taking that and using it to texture all sandy surfaces in racing games.
Then they could make better use of techniques to make the sand appear to move when you drive over it.
In other words, the next gen games won't be so focussed on "more dots!!!!" but "more detail to shove in those dots".
Instead of the flat, blocky, uninteresting spectators in GT5, we could have 3D people with more complex behaviors and movements.
And hopefully, PD makes them much less noisy