I find it funny people comparing racing sims like GT5 and Forza to Mario Kart 8 to downplay the game. Sorry guys, racing sims are much less demanding on hardware than what we have here with Mario Kart 8, which is why those games are running with AA and Mario Kart 8 isn't. You are all comparing apples to oranges.
A much better comparison would be kart racing games to Mario Kart 8, and MK8 blows out of the water every last-gen karting game, running at full 720p with 60FPS to boot. Wii U is more powerful than a PS3/360, but it's not anywhere near comparable to a X1 or PS4, people expecting this game to run at 1080p were delusional, specially considering last gen karting games ran at 30FPS and 640p(Sonic and Sega All Stars racing for example, and that still looks worse than Mario Kart 8).
