I am going to go for 50-100 years.
The first step in audio will be something that I've mentioned a few times in the past.
Sorry Axiom, but the future in audio for larger groups (not just a single listener) is an active laser array. You enter the room and the system starts tracking your ears. It them focuses sound waves via lasers directly to your ears. That means that each person can get either slightly or dramatically altered sound based off of their head placement.
For example, you are sitting forward watching some chick flick called 'Ever, Ever, Ever After' and things are pretty much the same for all viewers, but you put in 'Star Wars EP:19' and during a battle scene, as you turn your head, the sound field changes specifically for you via your portion of the laser array. You can even turn around completely and get full 360 degree discrete audio both horizontally AND vertically (a sphere of sound) all while preserving each of the other listener's audio experience. Stand up right as a laser blast is going by, and it will sound like it went right through you. Awesome!
Tied to that will, of course, be a full immersion video setup. Rooms will start to becoming more rounded with domed ceilings and curved walls. The system will rely on active panel displays (no projectors to seam up or place somewhere). You look around and are completely surrounded with the environment, even the boring parts of the two lover birds walking in a park in 'Ever, Ever, Ever After.' The floor will be, for some time, still a solid and flat surface. The video system will also be 3D, but not holographic yet, and each viewer will see a different 3D image customized to their vantage point. That technology for multiple vantage point, glasses free 3D is already being developed, so this should not be a problem for a group of people in 50-100 years.
After that, the jump will go from video rooms to the Holodeck. Full holographic projections using the same laser isolation sound system. The floors will dynamically move and allow people to interact with the space as well. This will initially be only in large commercial spaces and catered towards 30-60 minute "adventure" films for smaller groups. Mainstream actors will not be needed as the viewers are the actors. This will prove to be a gimmick for consumers, but governments will use them for simulations.
In about 150 years, after the actors protest not being useful, full on "beam the data into your brain" tech will come along. You will relax in your favorite comfy chair and have the images and video shot right into your brain for a full "this is real" experience. (Side note: Sony has had a patent on this concept for a few years.) This will soon lead to the "Total Recall" type of system that instead of letting you experience the story in real time, implants the "memories" into your mind. It only needs 5 minutes from start to finish. This soon leads to "Matrix" style data learning, but knowing Kung Fu in your mind, does not mean that you know it in real life.
