I seriously doubt it. But I would love to see the 5S sport 4K video recording. For starters that's a feature that other smartphones don't have right now. H.265 (which is likely to be the recording format) was already ratified earlier this year. Apple pushed H.264 pretty hard when it first came out, so seeing them do it for H.265 is not a huge leap. Especially since they own some stake in it. So it may be possible there is some new hardware encoding/decoding built into the new chipset.
Plus the camera itself, 4K is 8 megapixel video. Although it would probably require a new sensor, we know Apple is going to be putting in a new sensor anyway. So even if they just stick with a new 8MP sensor rather than go higher (which would be smart IMO) they can always sell it based on the 4K video resolution rather than increased photo resolution.
The only thing I can see as being an issue with 4K video would be the lack of displays. It would certainly look great on their retina displays, but for everyone else they would need to downrez the video to 1080p. That's an extra step. But 1080p from 4K native will look better than native 1080p.
Plus the camera itself, 4K is 8 megapixel video. Although it would probably require a new sensor, we know Apple is going to be putting in a new sensor anyway. So even if they just stick with a new 8MP sensor rather than go higher (which would be smart IMO) they can always sell it based on the 4K video resolution rather than increased photo resolution.
The only thing I can see as being an issue with 4K video would be the lack of displays. It would certainly look great on their retina displays, but for everyone else they would need to downrez the video to 1080p. That's an extra step. But 1080p from 4K native will look better than native 1080p.