i think you should take the best looking xbox 360 release games and not the worst because i think people also look at the best wii u release games to compare them with actual games. otherwise you could even take 360/ps3 games from 2011 or 2012 which still don't look much better.
i would look at pgr3 and such games and compare them with xbox games and then you see there was already a big difference at release in some games.
you should also mention that even if the 360 or ps3 launch games didn't have graphical improvements except the resolution, that this alone was much more to calculate for the console.
so, i think we will get nice looking games on wii u, not only artistical, also in raw graphical aspects better than every ps3/360 game but i still think the launch games we know about compared to 360/ps3 games are worse graphically as it was with 360 games compared to xbox games.
