That the Wii is a social game console is completely unfounded. There are a TON of solo games for the Wii that are really good and get played a lot. I personally love the Rayman's Raving Rabbits set which can be two player but only in a limited way. There is also the Ledgend of Zelda which is only one player. There are a bunch of others that I don't play but that I know are well liked.

Also the DS is a social game because it allows for playing of the multiplayer games even if other people don't own the game. I love playing Bomberman with several people on the DS.

Just because you only playing the Wii with other people and the DS by yourself doesn't mean that's how the systems are designed.