i looked some new WiiU footage
Ninja gaiden seam sub720 with poor AA (wait retail version for confirm because is strange, is under the PS3/X360 version)
http://www.youtube.com/watch?v=FAreMlwF-3A&feature=plcp
and Tank tank is 1280x360 no AA (+ probably 850x480 on gamepad. it's surely multiplayer mode with aproximatly the same pixel number on TV and Gamepad)
http://www.youtube.com/watch?v=Eo7wPaz4LDQ&feature=plcp
http://imageshack.us/a/img99/1466/tanktank.jpg
welcome to the nextgen sub720 world
EDIT:
i verified another time the NG video, it's probably dynamic resolution for stabilize framerate
sometimes 576p, sometimes 630p but i have grabed one 720p screen too