I don't buy the idea of audience fragmentation being a problem. The whole idea of a capitalistic profit orientated business is to seek profit where-ever they can. If they can find an untapped market and sell even more copies across a wider base they will certainly do that. A port isn't a problem really if theres an audience they are targetting.
I think the real problem isn't the development issues across the different platforms its a marketing issue. Both HD consoles can use the same advertisement but you're really pushing far into false advertisement territory if you include the Wii on one which supposedly includes gameplay. In addition to this I would suggest that they feel a lot of Wii games aren't as good to advertise on a visual medium in that they feel they may turn people off due to 'inferior visuals'.
Tease.
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