Techflash has a report of the amount of physical space you will need when using Natal. Craig Mundel, the company’s Chief Research and Strategy officer, held a discussion at the Microsoft Redmond campus and revealed Natal can ‘see’ an area up to four metres wide, around 2.7 metres high and 4 metres in depth away from your TV set.
This information has not been confirmed by Microsoft and the wording of the article is confusing. It is entitled “how much space you will need” which indicates you will require 4 metres of clear space, and indeed a quick Google reveals many other sites are stating this as fact.
I think the Techflash article may be badly worded, surely Microsoft are not expecting people to clear their living rooms to use Natal? Although the title states 4 metres is a requirement, it does not say this in the main body of text, just that 4 metres is the maximum distance Natal can ‘see’. I expect Microsoft will be clarifying the matter as soon as they see the panic on the interweb.