I too think that RE4:Wii is by far the superior edition just because of the controls and can never go back to playing the game on a normal analog controller but I don't see RE5 coming to the Wii ever.
It's easy to port something from a less powerful system (GC/PS2) to a more powerful system (Wii) but porting something from a more powerful system(360/PS3) to a less powerful system (Wii) is just like making an entirely new game. At that point, it's more worthwhile to just make a new game so that you won't have to deal with an inferior version (because the two version would be more different than you think in more ways than just graphics).
That being said, I could see an RE series coming exclusively to the Wii. I wouldn't hold my breath yet on it being the main series nor do I think it will be a rail shooter like RE:UC, but the Wii is being good to Capcom and Capcom will be good to the Wii.
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