by the time that actually happens though, the next new things will be coming out for sony and MS. so as people are being amazed by the jump in technology for the ps4 and 720, I doubt many people are going to be saying "hey you know what the wii-u finally is pushing out things much prettier than the old ps3 could."
I think people really exaggerate what the next gen visual leap will be. I have no doubt in my mind, that it won't be remarkable. Next gen will be a features, not graphics.
There's actually not that much further that they can go, unless they want to spend years and years and years making a single game world, to potentially have it flop or be pirated by those with the "devs don't deserve my money" mentality.
This generation was a decent size leap, but all it did was jump up into PC level visuals and if they bring out something super duper, it's just going to overheat.
WiiU will be a perfect example of where console visuals are going.
My instant game collection - http://tinyurl.com/dxq27an