Even if you have 4K content and sit close enough to your TV to "notice" extra detail it's not like the extra detail is really going to improve the image quality as much as the contrast difference between a compromised LCD and a high quality plasma screen would. Who cares if you can see the droplets of sweat on people's skin.
Cnet once cited a research bureau that empirically found that most people care more about a high contrast ratio and color accuracy than about resolution. The difference between the already very high 1080p resolution and 4K is especially redundant.
-And add in the fact that 1080p material (aka 99% of what we currently have) looks worse on a 4k display (I don't care how crazy you upscale it, content always looks best at its native resolution)
-And add in the fact that the new consoles that we will live with for 6+ years only have the power to do 1080p
-And add in the fact no solid platform for 4K distribution for new releases (aka a 4K Blu Ray) exists yet
-And add in the fact that cable and satellite providers barely provide 1080p (and often its compressed to hell)
Put all together, and honestly no one should be being 4K TVs right now unless all you plan to do is game on it with a $2000 PC.
Sad part is that nerds like those on this forum are used to judging things on specs: "This Seiki has twice the resolution as the Samsung plasma so it must be better." You can't do that with TVs, closest you can come to it is judging based on black levels (something the plasma wins every time).
I get if someone is a gamer and they want a 1080p Sony set just to game on for the low input lag, but anyone else who cares about picture quality for TV and movie viewing needs to buy a Samsung plasma this year and thank the gods they got a shot at one before they go away.