4K has been the holy grail for home video (in my opinion) as 35mm film has approximately the equivalent of 4K of information. It's also the resolution that most major productions are finished in. Even things shot digitally at 5 or 6K are almost always going to be downrezed to 4K for finishing. (which can often look worse than if it was simply originally shot at 4K!)
This added resolution will be most apparent in wide shots. Close-ups will look virtually identical, but in wide shots the difference should be very impressive.
I have to giggle a little bit that "4K" is the hot new thing in 2015, as I've been working in that resolution since 2000! (it should be pointed out that UHD is actually "faux K", as 4K is truly 4096, not 3840, but the idiocy that created the HD format at 1920 dictates this next evolution.
...and yeah, it's been a LOOOONG time since I've posted around here.
