Video comparison of a Wii game (on the right), that was ported to the Xbox 360. This is No More Heroes: Heroes Paradise, a game with intentionally low-fidelity "punk" visuals. Looked good enough on the Wii for me.
This might be the originating site. Whether it is or isn't, it also has a comparison of loading times, not that loading times was a problem No More Heroes had.
No More Heroes: Heroes Paradise is being released in Japan on the Xbox 360 and PlayStation 3. The original Wii game, a cult favorite, spawned a sequel, No More Heroes 2: Desperate Struggle, which was released in the U.S. on the Wii earlier this year — and reviewed by Kotaku.
UPDATE: Games reporter Matt Hawkins clarifies that we're looking at the "censored" Japanese version of the Wii No More Heroes, black pixelated blood and all, which is why it looks different from the U.S. version.
(Via Matt Hawkins.)