4k is coming and it is coming fast. Broadcasters and set mfrs are now in a dead-heat tie on developing the technology. It took 10 years for set mfrs to catch up with broadcasters in HD. Mostly learning how to make flat plates and decide on a single format.
And the testing is already on the air in some places. Lot's of little tidbits in this article;
http://svgeurope.org/blog/headlines/...sses-the-test/
Lots more to learn to ship it by satellite, OTA, cable, etc. Bandwidth is an issue by multiples.
And then there is 8k floating out there. If 4k is 4 times HD, 8k is 16 times HD. Save your HD sets...future collectibles sooner than we thought.