Now that we have lasers covering all three color (RGB) I'd like to see a display and projector technology develop around lasers.
Imagine a 10MP-20MP projector that uses additive color instead of the much more power hungry subtrative color. Depending on the amount of power the chip would be expected to put out it might have a big heat sink, water cooling, Peltier cooling, or no special cooling at all. In a home environment with a short distance to the projected surface the simple cooling system might be all that's needed as the average power output might well be less than 30W, but in a movie theatre, where the distances are greater and the projected image is also greater, an active cooling system would probably be needed.
Now, for me, the real sweet thing would be the real high resolution capable of displaying my 1Ds Mark II images at full resolution.
I know, I know, I'm dreaming right? Well not too much -- I've worked in the semiconductor industry for most of my adult life and fully expect such a chip to be developed within the next 10 years and hopefully sooner rather that latter.
In addition to still image projection I expect all movie theatres to switch over to digital projection within the next 10 years and also expect most movies to be shot in digital with quality greater than 35mm and perhaps better than 70mm. Theatres would bennefit from this as they need to stay ahead of home theatres...