This is really exciting news. Everything has been moving to digital delivery of late, with higher compression, less quality and less features, but it is good to know that there will be a 4K disc based format which will deliver the best quality.
The only bad news is that it does not seem to include a 3D spec, which is likely a bandwidth issue, though it will be able to do 60P (hello Avatar in 60P). The spec has not been finalized but will use H.265, and will have a 66GB dual layer and 100GB 3 layer formats, and can even do 10 bit color and a wider color gamut as well as high dynamic range! It also will have a digital copy process to make local copies to a hard drive, likely in a specifically designed player.
Now I won’t be moving to this anytime soon, as I just got a 65″ 1080 display, and didn’t even consider 4K for lack of content and not knowing how 1080 will look blown up to 4K (I am assuming not good).