According to latest interview with Masaya Maeda from Canon Japan, Canon is currently working on a new 4K camera to compete against Panasonic GH4 and Sony A7S. This means Canon EOS-1D X Mark II will be released soon with 4K.
From dpreview interview:
How are you addressing the demand for compact, 4K-capable cameras like Sony’s a7S and Panasonic’s GH4?
Naturally I can’t give you details of our future plans but we are fully aware that such requirements exist in the market. We’re currently in the process of investigating, mainly to satisfy the needs of news media, and we have every intention of addressing this need in future products.
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