I think it's actually very easy to advertise Wii to non-gamers because of it's universal nature. Plug a core game, plug a "simple" game, plug a Wii channel.
Kid comes in the door. Sees a blinking light on the Wii (or something) indicating a message is waiting for him. TV comes up:
"Bobby, Meet me at 7 o'clock sharp for tennis. Love, Mom." Kid smirks.
Cut to them playing Wii Tennis, mixed with game footage.
You can change the message to anything you want, from anybody. Pretty easy to tap into parents and girlfriends this way, I think.