I dont think MS puts "faith" in anything. They have a team of calculating machines that determine the best possible course of action. Natal is already a success, we just don't know it yet.
Windows Vista was part of the plan too. Frustrate users to the point when Windows 7 comes out which fixes Vista issues, everyone will run to the store to buy it.
Zune too was part of...ummm...yeah someone screwed up there. :)







