That´s what I´ve been trying to tell people all the years. A lot of people say that the Wii had cheap technology, which it only has regarding graphics. It is not cheap to develop a motion control system. In my opinion, the problem for MS/Sony now is that they have to top Nintendo´s motion control system, which might make it expensive. It has always been difficult to release an extra hardware for a console that every developer supports, because at the beginning, the userbase will be very small. Yet, people buy Rock Band/Guitar Hero for hundreds of dollars just for one game series, so maybe thinbgs have changed. However, I am still sceptical about Natal moving that much hardware.
edit: a perfect example for this is motion control plus, which has not been huge yet.
