zzoo,, I wouldn't even fool with 4K right now. No real source content, no real 4K 3D (all 1080p), and really HDMI 2.0 is a waste when Displayport 1.3 has twice the bandwidth. A lot has to be decided on still with 4K.
I am personally building my mini-theater around the best 1080p projector/screen for the next 3-5 years. That way the screen is there and the projector mount. Pop a new one up when the 4K smoke settles.
My thinking is that 4K won't be around that long and the same with 4K Blu-Ray. Sharp has shown 2 years in a row 8K TV's. NHK of Japan is partnering with Sharp and has already practice run 8K streaming. You need 8K bandwidth to do true 4K 3D. Oh and you have to make sure your receiver is HDMI 2.0 compliant because the new 4K TV's do 60hz as opposed to last years models that could only do 30hz.
See what a pain in the ass 4K is and going to be.
Not to mention the amount of backers on HVD side of things: http://en.wikipedia.org/wiki/Holographic_Versatile_Disc
Yeah...1080p for a while....