Mario Kart Wii apparently has outsold both console versions of GTA IV.

[noname2200]

Don't start celebrating just yet. GTA IV is the Game of the Generation. Mario Kart Wii sold over a million on the Wii, so it is officially a Non-Game. Comparing their sales is therefore a comparison of apples and oranges. Ergo, GTA IV is still the best-selling game this generation.