The fundemental mistake Seam Maelstrom is making is that he assumes that motion controls are the principal reason that big name core ip (Bioshock, Assasins creen etc) are not ported to the Wii. From this he reasons that having disparate input strategies for the HD consoles will split the market. As games will not be interchangable.
The actual reason that the Wii gets so few ports are to do with the systems capabilities. The asset pipeline domiates game development and the substantially different capabilities of the Wii dictate a completly different pipeline. This and Publishers reticence to spend money on M rated titles for the Wii because, rightly or wrongly, they think it's toomuch of a risk.
HD consoles have proven performace in selling these 'core' games and this will not change because of different controllers. User input is such a minor part of development cost that supporting three different controlers is a small expense.
