Reggie promises that third-party titles on Wii U will look at least as good as their counterparts on the other systems.
"Most" of the footage shown representing third-party Wii U games featured in Nintendo's press conference are apparently from Xbox 360 and PS3 versions. In an interview with Gametrailers' Jeff Keighley (at 4:33), Nintendo of America's Reggie Fils-Amie confirmed that the videos were from other consoles, and explained that it is because the system is "a year away."
When asked if the games would look "as good" or "better" than the versions showed, Reggie noted that the graphics are ultimately up to the third party developers. He reinforced that the system is 1080p, and is capable of providing visuals on par with Sony and Microsoft's consoles.