There is UHD in the works; ultra HD @ 7680x4320 and 3840x2160 resolutions. It will probably take a very long time for that to migrate over to HDTVs. Even as of today there is really not enough bandwidth to broadcast programs at 1920x1080 resolution without a lot of video compression. The more compression you use, the worse video will look. If you ever streamed movies from NetFlix and compare the quality to movie played back on Blu-Ray you should notice a difference. Plus some people complain about lag because the movie stops playing the movie is not being streamed fast enough.
Internet speeds has come a long way from the old 56.6kbs standard of "Ye o' phone modems", but they still have a very long way to go for even the lower end of UHD because the higher the resolution the more bandwidth you need. 3840x2160 resolution has 4 time the number of pixels compared to 1920x1080. That's about 8.3 million pixels vs. about 2.1 million pixels.
DVD movies basically have a resolution of 720x480 and are stored on 8.5GB discs. Blu-Ray movies are basically 1920x1080 resolution and are stored on 50GB discs. Blu-Ray resolution is 6 times greater than DVD resolution and the storage capacity of a Blu-Ray discis almost 6 times greater than DVD (about 5.9 times). The lower end of UHD is 3840x2160 resolution which is 4 times greater than HD as stated above. That would mean movies would need to be stored on "Ultra Blu-Ray" discs with a capacity of 200GB.
I'm not exactly sure, but I would guess that NetFlix compresses a 2 hour movie down to around 1GB. A Blu-Ray movie would probably be compressed to around 6GB. A 2 hour "Ultra Blu-Ray" movie would probably be around 24GB. I'm not sure many can download 24GB of data in two hours. It's going to be a very, very long time for such band; if ever.
Right now it is possible to stream an "Ultra Blu-Ray" movie, but you will need a T3 line which costs more or less $4,000 per month. A T3 line can transfer 44,736Kbps. That's kilobits per second, which works out to about 5,460 kilobytes per second, which translates over to about 5.45MBps; megabytes per second. At maximum speed it would only take around 1.22 hours to download 24GB of data which means it should be fast enough to stream an "Ultra Blu-Ray" movie. Since Netflix would also need to pay $4,000 per T3, don't expect your movie streaming subscription to stay at $8 per month; it will easily jump up to over $100 per month. Also add the $4,000 monthly charge for your own personal T3 line.