Just did a more extensive breakdown, and it should further emphasize the gradual, slow, but inevitable movement towards multiplayer and away from single player focused games.
http://vgchartz.com/games/index.php?name=&console=NES&publisher=&genre=&keyword=&order=Sales
The NES top 20 sellers. 1 of 20 was multiplayer focused: Ice Hockey.
http://vgchartz.com/games/index.php?name=&console=SNES&publisher=&genre=&keyword=&order=Sales
Again, the SNES top 20 sellers. 3 of 20 were multi player focused.
http://vgchartz.com/games/index.php?name=&console=N64&publisher=&genre=&keyword=&order=Sales
The N64 top 20 sellers. 6 were multi player focused. Specifically, Mario Kart 64, Goldeneye, Perfect Dark, Mario Party 1, Mario Party 2, and Smash Brothers. You might also inlude Waverace 64 or Starfox 64, but those are both as much single player as they are multi player, in my opinion.
http://vgchartz.com/games/index.php?name=&console=GC&publisher=&genre=&keyword=&order=Sales
The Gamecube top 20 sellers. 7, perhaps 8 of the 20 were multiplayer focused. Specifically, Mario Kart Double Dash, SSBM, Mario Party 4, Mario Party 5, Mario Party 6, Mario Party 7, Super Mario Strikers, and Soul Calibur 2.
http://vgchartz.com/games/index.php?name=&console=Wii&publisher=&genre=&keyword=&order=Sales
The Wii top 20 sellers. 11 of the 20 were multiplayer focused. Specifically, Wii Sports, Wii Play, Mario Party 8, Mario and Sonic at the Olympic Games, Wario Ware: Smooth Moves, Big Brain Academy, Mario Strikers Charged, Rayman Raving Rabbids, Smash Brothers Brawl, and Carnival Games. I think Guitar Hero also counts, although it obviously features a robust single player mode, I consider it a premier "social gaming" game.
Let me shorten this just for emphasis. Percent of top 20 best sellers that are multiplayer focused, by platform.
NES: 5 percent multiplayer focus
SNES: 15 percent multiplayer focus
N64: 30 percent multiplayer focus
GC: 40 percent multiplayer focus
Wii: 55 percent multiplayer focus
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