I tried to sound proof it as much as the space allowed with sound proof insulation. However if you don't go with separate floating inner walls and double doors bass will get through anyhow, plus the sound travels through the air heating/cooling ducts.
It's plenty to keep sound out anyway, I can't hear the air conditioning turning on while watching a movie. Another thing with projectors is you always have a fan, find one with as little fan noise as possible. RED was hinting at a projector where the lamp could be in a different place with the light going through an optical cable.

I believe you actually did not get it.  The effects that are happening are illusions that appear to extend beyound your TV not just projecting an image on a wall.  If you watch the videos carefully, when explosions or shots occurs, they appear as if they are happening outside of the game.  Think of it as a low budget 3d setup without glasses.  As stated before, this type of tech you actually have to experience in order to get a feel of what it is doing instead of watching a video as its harder to get a good feel for the effects.

What kind of development resources do you think extending the scope of view would have? Do you think devs would go for this if it is an exclusive feature that is optional? If it is easy to do and isn't a huge drain on the system then fine, but I would like to know.

Yeah there's the catch. If it comes with an SDK for a few simple universal effects they migh do the effort to trigger simple motion effects, color flashes, objective markers, snow, fire, etc.
But for game world geometry extending beyond the tv it would need more work then adding a 3D mode. Suddenly the field of view is extended by more then a factor of 3. (42" to 140" at the same scale) That needs a lot of work in the game engine. Probably not going to happen but for a few exclusives and then it would still take a hit on the visuals in the main view. Maybe it will get it's own child of eden / geometry wars type of game.

That's how I feel, and while the shooter they demoed in that video presents a very exciting feature it might be too demanding or outside of the interest of most game studios. For smaller titles though, like you mention Geometry Wars, it would be pretty amazing and still obtainable. I could imagine any stationary field game benefiting from this effect. The rest might have to settle for enhanced visual effects. A Call of Duty might include flashes from the mussle, that shaking effect in the video, fire glow, flash bombs, grenades, near death red vision, and hit detection. A racer would have weather effects. An Elder Scrolls could place the HUD on the wall instead of the screen. All seem very promising.

For more than that, the problem is these games need to work as multiplats so screen extension is a drain on resources it just isn't going to happen outside of some easy to make effects. Either way I am still very impressed by illumiroom, it is the best looking ambiant enhancement to date and will look great no matter what, even if full range view is too lofty to fit into the industry.

I doubt a thing like this comes cheap and will most likely price itself out of the market. If MS includes it with every Xbox, then I'm not sure how much they are going to charge for it or lose on the system's hardware. Then there is upkeep costs for the device. I'm interested in where they go with this.