I'm all ready to jump on the 4K bandwagon with the RED, but I don't see it being commonplace in people's homes as far as TV goes anytime soon... and I'm OK with that.
On computers maybe. And certainly digital cinema- I am not impresed by recent moves to shoot feature films with existing digital cine cameras, which are all shooting more or less 1080P, while film scans continue to extract usable detail at 4K.
Some of these films may not stand the test of time if and when we transition to a more detailed format... which is why I'm planning on shooting 4K even without a massive infrastructure.
It's easier to convert a BD-ROM or HD-DVD at 1080P from a 4K master than it is to create a superior quality 4K release from a 1080P master 😛
In the meantime, if I have anything that requires it, then the detail is there for future use 🙂