The announced development of a 4K Canon EOS DSLR could make some specs that come out hard to decipher. I believe a high megapixel EOS body is coming. The question is whether it would be the 5D3 or the new 4K DSLR.
4K video has 4 times as much video data as 1080p (4K is approximately twice the width and height of 1080p).
If 1080p requires an 8.3MP sensor, then 4K video requires a 33.2MP sensor.
And on that note, I wonder if the D800/A99 (or A9X?) from Nikon/Sony will also try and do 4K video (given that all of the rumors are saying that the sensor will be over 30MP.) If so, I hope that the Canon 5D3 is able to come in at a price point at around half of what gets offered there.