With the advances in technology it is becoming more and more possible to setup a wireless home cinema system in your home without having to run lots of cables around and start chasing into walls and ruining your decoration.
At the time of writing the technology in our opinion is not quite good enough for wireless video but wireless audio is definitely a viable solution if you are not going to look at too much of a high end system.
Wireless Home Cinema Video
The reason wireless video is not viable at present is primarily due to the bandwidth required and given the detail of the formats are increasing as well it makes it hard for technology to keep up. High definition content holds a lot of information and to transmit that real time in just not practical.
You can currently get some wireless projectors and these can either work as real time devices or as upload and play style. The upload type store wireless uploaded content and then play it from their internal storage. Real time devices literally play the content as it is being transmitted. There is usually a small delay between the transmission from source to projector and this means that it's only really practical to use this type of transmission for static images such as power point presentations; it is currently not able to deliver motion with any degree of quality.
It is slowly becoming more possible on lower resolution screens and close procurement of transmitter to receiver. How long it will be before we see full high definition home cinema projectors I'm not sure but it's on the horizon.
Wireless Home Cinema Audio
Wireless audio is becoming quite common nowdays especially in town apartments where it may not be practical to run cables around. You will find that there is the possibility for both wireless source material to be transmitted as well as wireless audio signals to be sent to speakers.
In general audio signals carry a lot less information than video and so this means the bandwidth limitations are not so much of an issue as with video.
So how long is it going to be before we start seeing full dedicated wireless home cinema systems?
Well I still think it will be a while for dedicated home cinema systems if we even see them at all. The reason for this is because with a dedicated home cinema you are naturally going to build the room as well and so you can always plan to run the cables that you need which will always have a better transmission path than from wireless.