Canon USA at NAB 2013
Canon's focus here at NAB 2013 is definitely 4K acquisition and broadcasting. They have a big theater and ongoing presentations about the benefits of acquiring your content in 4K resolution.
A lot of people, including myself, don't think 4K will even become a mainstream thing inside peoples homes. The size of screen you'd need to see the difference between 4K and 1080P in your home would eliminate most potential customers. Think of it like a 1080P vs 720P 32″ television, there's just no discernible difference when viewing 1080P content. Another big issue with 4K in your home is streaming content at that resolution. As on demand internet content services become more popular, there's only a handful of people in the grand scheme of things that will have the bandwidth necessary to stream 4K resolution reliably.
Acquisition does have a lot of merit. Canon was very much pushing the idea of cropping, zooming and having more options when editing your film. They showed a lot of examples of 4K content being zoomed 200%-300% and outputting to a 1080P signal, and the image was still quite stellar.
Beyond the cost of a 4K display, the workflow with 4K content needs improvement. There is a lot of software and hardware talk here at NAB to correct this area of the equation.
Will we see 4K in a DSLR camera other than Canon EOS-1D C? One day, though I don't think it will be soon. A drop in price-point for Canon is something that would be welcomed. The $25K+ C500 is a big jump from the $15K C300.
The 4K and 8K resolution is beautiful on the big screen, just don't expect it to become mainstream in your home. Your local movie theatre is a different story.
Canon EOS C300 $13,999 (Save $2000)