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The next Nintendo console will have a "gimmick". Nintendo has already basically said so ("new game concept", "upgrading hardware is boring"), etc.
Nintendo is not going to simply do the same thing Sony and MS do. I think we may as well just accept that for better or worse.
Truth be told, I find Nintendo games looks pretty damn good on the Wii U as is. This isn't like the Wii vs. PS3/360, where Wii games looked like garbage on an HDTV set next PS3/360 games.
Wii U games still look nice if the effort is put into them.
I wouldn't honestly be all that choked about a platform in the 1 TFLOP range with 3-4GB of RAM for games.
I think Nintendo's plan is they will roll the dice again on some Miyamoto-approved gimmick. If said gimmick doesn't pan out this time, they still can fall back on the unified platform thing (play the same games at home or on the road) at a low cost.
