has the following to say about parts and dates for Project Natal. Some of it is quite confusing, specifically the phrase, "a new version of the Xbox 360 console". As far as anybody is aware, Natal will work with all current Xbox 360 versions.
"Aptina (Imaging Corporation) has won exclusive rights to supply 1.3-megapixel CMOS image sensors (CIS) for a new version of the Xbox 360 console under Microsoft's Project Natal technology, and shipments of the new Xbox 360 are slated for the second half of 2010, according to industry sources in Taiwan."
Well, at least we know that you only need 1.3mp sensors.