Thanks Xenplay. I was right that there are more platinum selling Gamecube games than 2 or 3. In America alone, there are 6: SSBM, Mario Kart, Super Mario Sunshine, Wind Waker, Luigi's Mansion, and Metroid Prime. Including Japanese sales there are 12: Mario Party 4, Mario Party 5, SA2:B, Star Fox Adventures, Animal Crossing, and Pokemon Colosseum. With the addition of European sales I'm sure a few borderline games have sold a million by now.
Comparitively, according to that same chart, the XBox has 4 platinum selling games, 3 of them in America alone: Halo, Splinter Cell, Dead or Alive 3, and Project Gotham Racing. The PS2 has, by my count (I might have missed some) 31 platinum selling titles- a lot of them sold like crazy in Japan and then little more than 10,000 here.