This is a long read people, but it has some information on Natal that I didn't find yet when doing a search in the forums.

Some advice for any Xbox 360 owners thinking ahead to the launch of Microsoft's Project Natal later this year: You might want to see if you'll need to reconfigure your living room. After all, the motion-sensing control system is no sit-on-the-couch experience. You'll need some space to move your body and swing your arms without banging into the coffee table.

To be precise, you'll want to clear an area extending at least 4 meters (a little more than 13 feet) away from the television. That's the back edge of the space to be taken into account by the Natal sensors. In terms of width and height, the field of vision naturally expands as it moves from the Natal device to that back edge, ending up a little more than 4 meters wide and 2.7 meters high (about 8 feet, 10 inches).

Those were among the tidbits passed along by representatives of the Natal team during a briefing for a group of reporters and bloggers Monday on the company's Redmond campus. The session was part of a day-long technology discussion held by Craig Mundie, the company's chief research and strategy officer.

Natal, announced last year at the E3 video-game convention, is due out by the holidays. It's Microsoft's effort to bring its own "natural user interface" to the Xbox 360. It differs from Nintendo's Wii and Sony's upcoming Motion Controller, in that the camera system senses movement without requiring the gamer to hold a controller. (However, one of the details that emerged from the session is that controllers and accessories can be used in conjunction with moving around to add even more elements of control to games.)

During the Monday session, we quizzed Don Mattrick, who heads the company's video-game business as its senior vice president of interactive entertainment. Mattrick said the response from consumers in testing of Project Natal has been "off the charts." Mattrick said he's excited about the types of experiences that game developers are creating with the system, declining to go into details. He noted that Natal is also getting interest from the broader entertainment industry, citing as an example Steven Spielberg's early endorsement.

The session included lots of technical details on the Natal device, including its three sensors for measuring the depth of the room, capturing the gamer's movement and ensuring adequate light. The machine-learning system can also tell where parts of your body should be even if they aren't visible to the camera, such as an arm tucked behind your back. (Technical phrase: "Extremity occlusion resilient.")

The Natal team says the device requires less in the way of processing than the average smartphone, because they wanted to leave as much processing as possible available to the game itself.

As for the price? Mattrick wouldn't say, but he predicted that it won't be as much as consumers who have tested the device might expect, given the amount of fun they say they're having. Microsoft has created the Natal device with off-the-shelf components, which has the effect of keeping costs down and positioning the company to take advantage of broader industry advances in vision technology and sensors.

"We're going to drive the business, and make it scale, and make it profitable," Mattrick said.

http://www.techflash.com/seattle/2010/03/notes_on_project_natal.html

I don't have enough room for that, unless of course I move my couch.

I'd have to get rid of my bed then haha.
Well, this definitely won't win Japan over.

Good thing my living room is pretty much designed to have lots of space like that

Well if you're going to be playing any multiplayer you may in fact need that much space.

Also of course you won't necessarily need the 13ft in order to play single player titles, but either way I am not sure something like or Sony's Move will work in my home right now since they both require plenty of room that I currently do not have.

If you move your bed, then you'll miss out on the Natal sexperience.

That would be an interesting "experience" in a game... I'm all up for role playing Shepard's love scenes with a few of the women

You'll need as much room as people playing Wii Boxing.

well i'm a bit over six feet tall so according to this:

To be precise, you'll want to clear an area extending at least 4 meters (a little more than 13 feet) away from the television. That's the back edge of the space to be taken into account by the Natal sensors. In terms of width and height, the field of vision naturally expands as it moves from the Natal device to that back edge, ending up a little more than 4 meters wide and 2.7 meters high (about 8 feet, 10 inches).

....standing 13 feet back the height of the field of vision is 8 feet 10 inches.  did the geometry on the situation and if i were to stand any closer than 8 feet 9.6 inches and the field of vision will be less than my height.

If we knew the FOV that Natal uses, we could make calculations.

like i said the the previous post, i used geometry.  http://en.wikipedia.org/wiki/Similar_triangles#Similar_triangles

i used the height and distance of natal given in this article ( the part where they said the back edge is 13 feet and has a height of 8 feet 10 inches).  then i used my height of ~6 feet to calculate how far back i have to be as a minimum for natal to capture my entire height.