It is rumored that Sony may actually release a 4K capable Playstation 4. They will possibly release a new PS4 with 4K graphics since this is not available in the current generation of Playstations. Not only will this new one have the ability to support 4K, it will have much more processing power in order for support for things that the current PS4 cannot do. This is a great improvement for consoles as many people are starting to own 4K TVs, but are unable to use the true 4K support with the original Playstation 4 as the GPU cannot support it right now, since 4K graphics need much more power to be supported and to be viewed without the user having any problems.
A reason for the new 4K PS4 could be because of the launch of the PSVR and so that the console itself has enough power to support the PSVR whilst playing games. Even though the current PS4 can most likely support the PSVR, extra power is always better, especially to ensure there is no lag or problems when using the VR headset. The new PS4 has been rumored to be announced just before the release of the PSVR, so that there is a console that can actually support the VR headset, and so that people can consider purchasing the PSVR. It is also possible that Microsoft will update the Xbox as well to compete with the updated PS4.
Whether Sony releases this new Playstation or not is also a question, but it is very likely that it will be released. As of now we have no clue of when this PS4 could release and how much it will actually cost, but if it does release, this will be a major improvement for consoles and could be a considerable purchase.