Not reading this thread as it's filled with stupid stealth trolls. What I will say is that you can't think of a price based on the price of current add on's
IE $150 HD and $100 Wifi. The very fact a 360 itself cost only $50 more than a HD that must cost MS about $20 max to produce means they're only selling these add ons for so much because they can and they don't care about if they're picked up or not. They're ripping the customer off but then who the hell needs to point that out? It's pretty obvious.
I don't know how much natal will be, whether they want to loss lead or make a profit from the get go, but people using current add on prices as a bench mark .... are well way off the mark!